FBH The end of the SAGA ?

[FrenchMike]

MY STORY:

I came upon this Forum 3 years ago after my in tank fuel pump broke.
I found advice here to have my pump quickly and cheaply repaired.

I too also had the strange Fuel Burning Heater (FBH) behaviour caused by the K bus.
(Which I have since disconnected.)

As a regular reader, I have noted lots of threads about FBH issues and in particular
that the PCB was reported as being non repairable.

The cold days made me inclined to study the question. I began by trying to collect information about the circuit diagram etc, (not very easy)

At first I thought the Interface IC bus was the culprit.
I ordered the genuine interface IC bus (ELMOS 10026B) from Hong-Kong,
but one month later, nothing ;they forgot to ship
Meantime, I bought the Riesler interface Bus describe by Keith Alexander .
I discovered than his Interface Bus IC was a (Melexis TH3122) similar
and more easy to get.

Next, I built up a test bench and established communication between my laptop and
the Webasto PCB.
However, there was a combustion air fan error. (running at max speed).
Tracing the PCB ‘tracks’, I discovered than the power Mosfet’driver was always
ON although the Micro bus line concerned was live .The link is in fact a SMD (surface mounted) resistor well hidden under a kind of sticky sealant (looks like meringue.)
The resistor was marked 4.75 kOhms but my multimeter showed infinite !
Strange ,I had rarely seen that before in my professional live.

Anyway, I quickly replaced it and …..everything worked …..

I opened a new thread on the forums to tell the news.

So, the only possible cause, was that the resistors were being attacked by a chemical agent from that paste (meringue).

(can you imagine how many Webastos this may have affected all over the world !!)

I would like to freely publicise this valuable information, in the true spirit of the ‘Forum’ and it’s ethos of sharing information.

Most members will be able to do the work for themselves ( or know a man that can!).
However, I can do the repair for others who don’t feel like tackling the job themselves

TOOLS NEEDED:

Low power soldering iron with thin tip correctly earthed.
Table magnifier,
Solder
SM (surface mounted) resistors 4.7 Kohm ; 47Kohm


PROCEDURE

Extract the PCB from the FBH (5 screws)

Pic 1
http://rovermg1.free.fr/rovermg/thumbnails/dyMLhkJ5bQ16KPOGQCDM.jpg (http://rovermg1.free.fr/rovermg/images/dyMLhkJ5bQ16KPOGQCDM.jpg)
http://rovermg1.free.fr/rovermg/images/dyMLhkJ5bQ16KPOGQCDM.jpg


Remove that sticky white paste and clean the area to show the resistors.
Take a measurement of them: two 4.75 Kohm and one 47 Kohm.


Pic2

http://rovermg1.free.fr/rovermg/thumbnails/wiwCm4tc4g92bR3csgOk.jpg (http://rovermg1.free.fr/rovermg/images/wiwCm4tc4g92bR3csgOk.jpg)
http://rovermg1.free.fr/rovermg/images/wiwCm4tc4g92bR3csgOk.jpg

If possible, built a test bench for checking out all the parameters before fitting on car.

Pic3

http://rovermg1.free.fr/rovermg/thumbnails/KyhACYUcOq1bfDSs8yx8.jpg (http://rovermg1.free.fr/rovermg/images/KyhACYUcOq1bfDSs8yx8.jpg)
http://rovermg1.free.fr/rovermg/images/KyhACYUcOq1bfDSs8yx8.jpg

Results

Pic4

http://rovermg1.free.fr/rovermg/thumbnails/mf7tiuGjTfi7LvgLmvvt.jpg (http://rovermg1.free.fr/rovermg/images/mf7tiuGjTfi7LvgLmvvt.jpg)
http://rovermg1.free.fr/rovermg/images/mf7tiuGjTfi7LvgLmvvt.jpg

Enjoy your warmer car :):lol:

Mike

[BigRuss]

Great work Mike :D:D:D

I will look forward to having a go at the repair, mines fine at the moment (touch wood) but there's quite a few members I know that have faulty ones.

Thanks for sharing your findings.:group:



Russ

[simpsora]

MY STORY:

I came upon this Forum 3 years ago after my in tank fuel pump broke.
I found advice here to have my pump quickly and cheaply repaired.

I too also had the strange Fuel Burning Heater (FBH) behaviour caused by the K bus.
(Which I have since disconnected.)

As a regular reader, I have noted lots of threads about FBH issues and in particular
that the PCB was reported as being non repairable.

The cold days made me inclined to study the question. I began by trying to collect information about the circuit diagram etc, (not very easy)

At first I thought the Interface IC bus was the culprit.
I ordered the genuine interface IC bus (ELMOS 10026B) from Hong-Kong,
but one month later, nothing ;they forgot to ship
Meantime, I bought the Riesler interface Bus describe by Keith Alexander .
I discovered than his Interface Bus IC was a (Melexis TH3122) similar
and more easy to get.

Next, I built up a test bench and established communication between my laptop and
the Webasto PCB.
However, there was a combustion air fan error. (running at max speed).
Tracing the PCB ‘tracks’, I discovered than the power Mosfet’driver was always
ON although the Micro bus line concerned was live .The link is in fact a SMD (surface mounted) resistor well hidden under a kind of sticky sealant (looks like meringue.)
The resistor was marked 4.75 kOhms but my multimeter showed infinite !
Strange ,I had rarely seen that before in my professional live.

Anyway, I quickly replaced it and …..everything worked …..

I opened a new thread on the forums to tell the news.
Some members were very interested ; and among them , ‘Simpsora’ who proposed sending me his PCB for testing and, if possible, to repair it
Guess what I found on his one? 3 resistors OPEN circuit (all located under the meringue substance)
So, the only possible cause, was that the resistors were being attacked by a chemical agent from that paste (meringue).

Anyway, the issue has finally been resolved for all of us.
(can you imagine how many Webastos this may have affected all over the world !!)

I would like to freely publicise this valuable information, in the true spirit of the ‘Forum’ and it’s ethos of sharing information.

Most members will be able to do the work for themselves ( or know a man that can!).
However, I can do the repair for others who don’t feel like tackling the job themselves (provided there aren’t too many!)

TOOLS NEEDED:

Low power soldering iron with thin tip correctly earthed.
Table magnifier,
Solder
SM (surface mounted) resistors 4.7 Kohm ; 47Kohm


PROCEDURE

Extract the PCB from the FBH (5 screws)

Pic 1
http://rovermg1.free.fr/rovermg/thumbnails/dyMLhkJ5bQ16KPOGQCDM.jpg (http://rovermg1.free.fr/rovermg/images/dyMLhkJ5bQ16KPOGQCDM.jpg)

Remove that sticky white paste and clean the area to show the resistors.
Take a measurement of them: two 4.75 Kohm and one 47 Kohm.

If open, leave them in place and solder the new ones on top of them . (more difficult for the small ones;
I soldered one end and made a thin wire bridge from the other end )

Pic2

http://rovermg1.free.fr/rovermg/thumbnails/wiwCm4tc4g92bR3csgOk.jpg (http://rovermg1.free.fr/rovermg/images/wiwCm4tc4g92bR3csgOk.jpg)

If possible, built a test bench for checking out all the parameters before fitting on car.

Pic3

http://rovermg1.free.fr/rovermg/thumbnails/KyhACYUcOq1bfDSs8yx8.jpg (http://rovermg1.free.fr/rovermg/images/KyhACYUcOq1bfDSs8yx8.jpg)

Results

Pic4

http://rovermg1.free.fr/rovermg/thumbnails/mf7tiuGjTfi7LvgLmvvt.jpg (http://rovermg1.free.fr/rovermg/images/mf7tiuGjTfi7LvgLmvvt.jpg)

Enjoy your warmer car :):lol:

Mike

PS: The ELMOS IC arrived today ; But I am happy to have won !

May I take this opportunity to thank French mike for all his work. I would also confirm that his 'how to 'is a genuine and 'solid ' fix for the PCB's . My own one is now working after 4yrs. of being redundant.

[foxspeed]

excellent work there - well done

need to check mine - it starts up but doesnt get hot so will to do some testing and see if i have chance this weekend to see what the fault is

[Jules]

So no Semiconductors failed then? Excellent Work Sir !
Hundreds of units must have been scrapped due to these resistors failing.

Amstrad products used to fail for the same reasons...................... The corrosive Glue
I used to repair Amstrad Satellites till 3 AM sometimes as they dropped like flies just after the Guarantee ended :shrug:


BTW standard 1/4 Watt resistors with legs could probably be used if there is space.
So don't worry about trying to source the exact surface mount components
They will solder on the the SM lands.;)

[Rufras]

Frenchmike, this is fantastic news as I found my failed FBH too big as a paperweight and hopeless as an anchor, well done!

[1gp]

:) fantastic work , people like you are a credit to this site . It just shows that things can be brought back to life , i wonder how many fbh have been scrapped when all was needed was some tlc. This is what this site is all about ....... spot on.... :)

[trebor]

this is a remarkable breakthrough, well done !

[Snagger]

Excellent news Mike well done ;) thanks for sharing the info.I can see Maplins being busy soon :D:D

Groover.

[mantianak]

Really impressive work there, well done. A definite money saver!

[NikTheGeek]

Can this be turned in to a pdf in the how to's section or download section? For future reference?

[bl52krz]

:) fantastic work , people like you are a credit to this site . It just shows that things can be brought back to life , i wonder how many fbh have been scrapped when all was needed was some tlc. This is what this site is all about ....... spot on.... :)
all i can say is "what a way to say thank you to this forum".
we have all benefited from advice on here, and i am sure we would all like to repay for the advice given for free. the job you have carried out has been an eye opener for all those with failed fbh. long may the athos of free advice continue.
could this be put in the "how to" section mods. please.

[bl52krz]

Can this be turned in to a pdf in the how to's section or download section? For future reference?
hi nick. you reading my mind?
just beat me to it.

[92 squadron]

:party:Great News I hope, as I am still unsure that this is the problem with my FBH but I am ready to give it a try.
I would like to be one of the first to give FrenchMike a little bit of business if he so desired, as I am as much use with a soildering iron as I am with knitting rubber hosepipes.
Please PM me Mike with your costings and details.
Could this be the start of something that even Webesco doesn't know about. I think we should keep quiet on this or Webesco could be buying him out!
Regards

[Lovel]

Mike,
Well done, its always very satisfying when you get to the point of that eureka moment isn't it.

I have a little clarification for you though. I have a brand new unused 75 FBH with obligitory faulty circuit board. The SMD resistors marked at 4.71K ohms are clear to see as they are identified with numbers and both of them pass the resistance test, however the 47ohm SMD is not marked with numbers, is it ? All I can see is a Brown coloured SMD in which I get a reading of 12.8Kohms which I believe may be the faulty one that needs replacing, photo attached. This is the SMD to the right of the resistor with yellow purple and green bandings? Can you confirm?
Regards.

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=4675&d=1266053929

[foxspeed]

these faulty "resistors" do we know of a place that can supply them ???

not really in to circuit baords and the like so plenty of info is a must :)

[Matt1960]

Mike,

What an excellent how to, and this could save members £200-£300.

This meringue substance. What would be the reason for webasto putting this on?
Also, could the sm resistors be replaced with normal ones for those of us that have poor soldering skills?

Matt

[FrenchMike]

Mike,
Well done, its always very satisfying when you get to the point of that eureka moment isn't it.

I have a little clarification for you though. I have a brand new unused 75 FBH with obligitory faulty circuit board. The SMD resistors marked at 4.71K ohms are clear to see as they are identified with numbers and both of them pass the resistance test, however the 47ohm SMD is not marked with numbers, is it ? All I can see is a Brown coloured SMD in which I get a reading of 12.8Kohms which I believe may be the faulty one that needs replacing, photo attached. This is the SMD to the right of the resistor with yellow purple and green bandings? Can you confirm?
Regards.

Hi,Lovel

The other resistor a replaced is the one marked 4992 (49900 ohms)
I put a 47 K ohms:

http://rovermg1.free.fr/rovermg/thumbnails/Tc5VigcrFPKZkls6BntI.jpg (http://rovermg1.free.fr/rovermg/images/Tc5VigcrFPKZkls6BntI.jpg)
I don't think capacitors or others components are concerned.

Mike

[FrenchMike]

Mike,

What an excellent how to, and this could save members £200-£300.

This meringue substance. What would be the reason for webasto putting this on?
Also, could the sm resistors be replaced with normal ones for those of us that have poor soldering skills?

Matt

Hi Matt,
Another one technology fault caused by long term corrosion !

Of course,one can replace the SMD resistors by normal ones but
not necessarily more easy !

Mike

[simpsora]

Mike,

What an excellent how to, and this could save members £200-£300.

This meringue substance. What would be the reason for webasto putting this on?
Also, could the sm resistors be replaced with normal ones for those of us that have poor soldering skills?

Matt
I think the sealant substance is put on by Webasto to hold the upright capacitors firmly in place. The taller capacitors could possibly 'vibrate' with all the vibrations created by road surfaces/ engine resonance etc . Could be wrong though!

[James.uk]

My congratulations Mike on solving a long term mystery! :bowdown:

Now to the practicalities for us who have no idea what elec components are or do.. :o

I realize that quite apart from the actual FBH there are other items = fuel pump, a fan blower of some sort, elec feed to some sort of glow plug, exhaust system, etc etc that may now fail to work due to lack of use over the years..

I don't mind paying, and am willing to travel to get my FBH working, but it may need more than just repairing the circuit board.. So is anyone planning on making a comprehensive repair service available in the UK for those of us who need it please?? :shrug: :o ..
..

[paulf]

Ive been following this thread also as my FBH didn't work and I wanted to repair the Pcb myself as i have plenty of electronic repair experience and refused to be beaten by the lack of back up provided by Webasto .However I managed to buy a cheap unit before I had got far with researching my faulty unit so never made much progress, it s great that French mike has managed to get to the bottom of the problem and come up with a solution, my faulty unit has an earlier Pcb that is not quite the same but im now going to have another go at it and am also happy to try the repair on other peoples pcbs.As I have a spare heater I can arrange a test rig if I get a spare fuel pump from somewhere.
Has anyone got any faulty boards that I can experiment with?.
I am sure others will be able to offer a service with the info kindly provided by Mike and would not want to take work from him but am happy to provide a service if its ok with Mike.
Paul
My congratulations Mike on solving a long term mystery! :bowdown:

Now to the practicalities for us who have no idea what elec components are or do.. :o

I realize that quite apart from the actual FBH there are other items = fuel pump, a fan blower of some sort, elec feed to some sort of glow plug, exhaust system, etc etc that may now fail to work due to lack of use over the years..

I don't mind paying, and am willing to travel to get my FBH working, but it may need more than just repairing the circuit board.. So is anyone planning on making a comprehensive repair service available in the UK for those of us who need it please?? :shrug: :o ..
..

[FrenchMike]

My congratulations Mike on solving a long term mystery! :bowdown:

Now to the practicalities for us who have no idea what elec components are or do.. :o

I realize that quite apart from the actual FBH there are other items = fuel pump, a fan blower of some sort, elec feed to some sort of glow plug, exhaust system, etc etc that may now fail to work due to lack of use over the years..

I don't mind paying, and am willing to travel to get my FBH working, but it may need more than just repairing the circuit board.. So is anyone planning on making a comprehensive repair service available in the UK for those of us who need it please?? :shrug: :o ..
..


Hi,James

Mechanical parts are rather robust !
Mine,after 3 years of non functioning, started on first time.

Mike

[Jules]

these faulty "resistors" do we know of a place that can supply them ???

not really in to circuit baords and the like so plenty of info is a must :)

CPC
RS
Maplin etc

Replacement resistors don't even need to be surface mount.
The standard 1/4 Watt axial type are easier to handle & solder;)

[foxspeed]

CPC
RS
Maplin etc

Replacement resistors don't even need to be surface mount.
The standard 1/4 Watt axial type are easier to handle & solder;)

ah i see - did look at them on the maplin site and wondered if they would do the same job - thanks !

[peter1961]

you know its guys like you 'and just a few others to mention' jules, big russ, raitslin' with your expertise who really get into the nitty gritty of things, that helps make this club what it is
a friendly sociable countrywide garage filled with idea's, views, know-how and advice, thats open every hour of the day and every day of the year.
what an excellent place to belong to.

a very big thankyou to you all

[Roverowner]

you know its guys like you 'and just a few others to mention' jules, big russ, raitslin' with your expertise who really get into the nitty gritty of things, that helps make this club what it is
a friendly sociable countrywide garage filled with idea's, views, know-how and advice, thats open every hour of the day and every day of the year.
what an excellent place to belong to.

a very big thankyou to you all

Second that:D And not forgetting the -Light- entertainment provided by the -sports- commitee;)

[James.uk]

Hiya Mike. :}

>>>Mechanical parts are rather robust ! mine,after 3 years of non functioning, started on first time.<<<

Thanks for that, and I hope you are right! Dunno how long it is, or even if ever, since the FBH woorked on my car, fingers and toes crossed that it will work once the circuit board been repaired.. :o

Come to think of it, I don't know how long my fuel pumps have been in the car either so must consider replacing those as well soon. :o

Roll on spring, so I can get out and about again without freezing!! :confused: :}
..

[FrenchMike]

PROCEDURE BEFORE SENDING YOUR PCB.

At first, manage to permanently connect a wire between pin 3 of the 6 pin plug
And earth in order to forget the +5 degrees limit.

You must hear the turbine increasing its speed and the circulating pump running

If the noise stops after 2minutes and 7 seconds, then,

The pump fuel is faulty or PCB (more likely)

If it stops after 4 minutes then the glow plug resistor is too high.
(More than 0.4 ohm)
And ignition aborts.

However, it is useful to test each component before deciding that PCB is faulty.


http://rovermg1.free.fr/rovermg/thumbnails/sf0bxOiSpkFGEqtdqYxm.jpg (http://rovermg1.free.fr/rovermg/images/sf0bxOiSpkFGEqtdqYxm.jpg)

Since the work is easier to do than it was first time (no more IC to replace),

My PRICE is 43 £ (one hour work) postage included

Input check ,repair, and outpout control with report.

Mike

[BigRuss]

Just in the process of testing a faulty board, have found up to now 4 faulty resistors all of which have been covered in the white compound.

Both resistors below the left hand capacitor and 2 under the right hand capacitor but not the bottom 4.7K one, that one's fine. The two that have failed on the right show signs of overheating, but the two on the left look normal.

Looks like any of the components that have been covered may be suspect.

Russ

[FrenchMike]

Just in the process of testing a faulty board, have found up to now 4 faulty resistors all of which have been covered in the white compound.

Both resistors below the left hand capacitor and 2 under the right hand capacitor but not the bottom 4.7K one, that one's fine. The two that have failed on the right show signs of overheating, but the two on the left look normal.

Looks like any of the components that have been covered may be suspect.

Russ

Hi,Russ

Forget overheating
Around the microprocessor,all the components work at very low power.
few milliwatts only.

Mike

[ianw]

I there been following this thread for a while now and i think all the info that u guys give is brilliant . i recently bought an fbh 98570B tested it the car by earthing pin3 it started its cycle then cut out i found the fuel pump was not pumping.tested the pump off the car and it seemed to work.from the info from u wise ones igathered it is the pcb:getmecoat: i have since seen another fbh for sale and i am considering buying it bmw x5 e53 will the connectors be the same and will have to 12v+to pin1 thanx

[tony_fry]

Don't think the connectors will be the same Ian

[Jules]

Mike can you apply your Magic out to sort the very common fault with Mk111 Satnav units. (ie LED staying on):drool4:

[FrenchMike]

Mike can you apply your Magic out to sort the very common fault with Mk111 Satnav units. (ie LED staying on):drool4:

Hi,Jules

I don't know the satnav and i haven't one but why not:

I guess they become faulty following a flood ?

You can send me one, i will have a look,one never knows.:}

Mike

[Jules]

No I don't mean mean flood damage unit's they are more often than not scrap.

Something corrupts the MK11/ Mk111 Flash memory/CPU if the Car Battery is removed less than 2 minutes after ignition switched off. (ie before Satnav has gone though it's shut down procedure)

Result is often that it will never shut down (LED stays on) and the PERM 12 Volts fed to it drains the Battery over 2 days (depending on Batt condition)

There you go ............a brief history.
If I send you a duff Mk111 this morning, can I collect it all repaired, this afternoon?:p:

[FrenchMike]

No I don't mean mean flood damage unit's they are more often than not scrap.

Something corrupts the MK11/ Mk111 Flash memory/CPU if the Car Battery is removed less than 2 minutes after ignition switched off. (ie before Satnav has gone though it's shut down procedure)

Result is often that it will never shut down (LED stays on) and the PERM 12 Volts fed to it drains the Battery over 2 days (depending on Batt condition)

There you go ............a brief history.
If I send you a duff Mk111 this morning, can I collect it all repaired, this afternoon?:p:

Well,if that involves programming tools,it is much more difficult !
I am afraid not to be ready for this afternoon.:D

Is there a Kbus link problem too ?

Mike

[foxspeed]

purchased a bmw x5 thermo top the other day to use as spares to fix my fbh - the unit was off a 2005 x5 - the circuit board still has that white silicone on :(

[ianw]

hi there fox speed are the connections the same as the rover fbh and what is the difference between the two units?

[foxspeed]

hi there fox speed are the connections the same as the rover fbh and what is the difference between the two units?

only slight differences

4 screws hold the fan unit on (5 on older rover thermo top)
glow plug fitting and retaining clip different
circuit baord looks the same - not sure on the "programming"

connections all look the same

i swapped over combustion chambers and glow plug (after de-coking them)

works a treat now

[ianw]

hi there foxspeed will the whole unit work with the existing 75 wiring if u plug in the 75 connectors if no what is diffrence.also are there any compatable heaters out there which will work thanx ian:confused:

[foxspeed]

hi there foxspeed will the whole unit work with the existing 75 wiring if u plug in the 75 connectors if no what is diffrence.also are there any compatable heaters out there which will work thanx ian:confused:

tough call mate - all the connections look the same - i would hazzard a guess the circuit board chip could be programmed differently - i didnt plug the x5 one i had straight in - i just took it apart and used it to repair mine

there are a couple of rover ones on ebay - quite cheap - was looking at those but decided on the x5 one because it was off an 2005 car and looked in good condition from the photo

the fan unit and heat exchanger look the same - so good for spares but as said its the elctronics - not sure how bmw wire theres up

sorry cant be anymore help

si.

[ianw]

thanx for the info foxspeed;)

[cusm]

Hi all i've bit the bullet and bought a soldering kit from maplins. But they don't do surface mounted resistors so my shout for help is where else can i buy them. Many thanks Stu.

[mamasboy]

Hi all i've bit the bullet and bought a soldering kit from maplins. But they don't do surface mounted resistors so my shout for help is where else can i buy them. Many thanks Stu.
Going to be doing mine this weekend, i'm going to use through hole resistors with thelegs bend underneath themselves - will do the same job. If you were being particular, break open almost any old piece of broken audio/visual equipment you may happen to have and rob one from there, they are common as muck:icon_razz:

[cusm]

Going to be doing mine this weekend, i'm going to use through hole resistors with thelegs bend underneath themselves - will do the same job. If you were being particular, break open almost any old piece of broken audio/visual equipment you may happen to have and rob one from there, they are common as muck:icon_razz:

Let us know how you get on and few photos of the finished job (for my benefit lol) would be great

[mamasboy]

Let us know how you get on and few photos of the finished job (for my benefit lol) would be great
Looks like the weather is stopping me getting home this weekend, looks like a job for christmas week, i'll get lots of pics if it'll help you.

[navrac]

Hi all i've bit the bullet and bought a soldering kit from maplins. But they don't do surface mounted resistors so my shout for help is where else can i buy them. Many thanks Stu.

PM me your address and I'll stick some in the post ( weather permitting). They come in packs of 100 and I've only got one FBH so I have a few spare!!

Also buy yourself a magnifying glass!

[mamasboy]

PM me your address and I'll stick some in the post ( weather permitting). They come in packs of 100 and I've only got one FBH so I have a few spare!!

Also buy yourself a magnifying glass!
Could I call on your kindness also? Got a couple of through holes but would prefer to use SMD's..

[HarryM1BYT]

A few words on SMD soldering technique might be useful....

I use a wooden cocktail stick to both remove a refit these type of components, with the point dipped in oil. With a good fixed manifying lens, so both hands are free and plenty of light. To remove, melt the solder on one terminal then push the solder out of the way with the cocktail stick - if its a two terminal device, melting the other end should then free it. Be aware that some SMD's are also glued into place, so both ends may need to be desoldered first, before trying to tease it away from the glue.

Fitting a replacement is a case of pinning the component in place with the cocktail stick (otherwise it will stick to the hot iron tip), while its ends are resoldered.

[cusm]

PM me your address and I'll stick some in the post ( weather permitting). They come in packs of 100 and I've only got one FBH so I have a few spare!!

Also buy yourself a magnifying glass!

Thank You very much
PM Sent:xmas-smiley-041:

[cusm]

I`m not the greatest at electronic side of things, it took me 6 months to design and build a very basic circuit board at school.

so all the help is greatly appreciated

[mamasboy]

I`m not the greatest at electronic side of things, it took me 6 months to design and build a very basic circuit board at school.

so all the help is greatly appreciated
Not convinced you're much good on a PC either - you PM'd me:icon_razz:

[navrac]

Yep mamasboy - send me a pm and I'll get some in the post.

[navrac]

In addition to Harrys advice on soldering the little resistors, you may find it easier to scrape the coating off either end of the old resistor and then place the new resistor using the cocktail stick method and then solder the new resistor on top of the old one. If you haven't got a good iron this is the safest method as it lessens the risk of damaging the PCB tracks with excess heat.

One other hint is to buy some soldering paste that is designed for soldering these little b@ggers with - you just put some on either end of the new resistor, plonk it on the old one, hold it in place with the stick and add heat.

[cusm]

Not convinced you're much good on a PC either - you PM'd me:icon_razz:


That was so you could send me a Xmas card. :xmas-smiley-041:

[mamasboy]

That was so you could send me a Xmas card. :xmas-smiley-041:
You've just ruined the suprise now:weihnacht2: Happy wotsit called....

[cusm]

PM me your address and I'll stick some in the post ( weather permitting). They come in packs of 100 and I've only got one FBH so I have a few spare!!

Also buy yourself a magnifying glass!



MANY THANKS
Received the resistors on Monday Was a bit confused at first as to why someone would send me an empty envelope lol.

Just have to work up the courage to do it now.

Again Thank you.

Stu

[mamasboy]

Recieved mine also,sorry for the tardy thanks - wife opened the envelope and thought it was empty and threw in recycling but I retrieved them!:D

[cusm]

So Mamasboy, when are you away to pluck up the courage to attempt it.
Maybe we should set up a web cam and do it together ( fixing the PCB, for the dirty minded amonst us lol) :getmecoat:

[mamasboy]

So Mamasboy, when are you away to pluck up the courage to attempt it.
Maybe we should set up a web cam and do it together ( fixing the PCB, for the dirty minded amonst us lol) :getmecoat:
Not sure about the webcam :p: but i'll possibly get to it next week and will happily video the whole thing and send it to you if that helps, i'm an ex electronic tech but dont think you'll have any probs so long as you can distinguish between the hot and cold ends of a soldering poker!!

[cusm]

Not sure about the webcam :p: but i'll possibly get to it next week and will happily video the whole thing and send it to you if that helps, i'm an ex electronic tech but dont think you'll have any probs so long as you can distinguish between the hot and cold ends of a soldering poker!!


That would be a great help,
I think I'll know which end is which when I burn myself lol.

[fegyvej]

Hi,
I have bought a Rover 75 in the summer and now in the first cold days I tested the FBH and it was just starting up and stopping after about 2 minutes. I could hear the fan and the water pump but no clicking noise from the fuel pump. I tested the fuel pump via giving +12V on it and then I could hear the clicking noise.
I searched the net and found this thread which seems to fit my problem, thanks to FrenchMike :}.
I removed the control circuit and removed the paste from it, then found the paste black above 2 resistors and one leg of the ELMOS. It looks like burned and I could see a very small amount of black thick liquid like thing when I removed the paste.
Unfortunatelly these resistors are different ones.
One is above and a bit left from the 47K one and the other is below and a bit right from the 47K one. The first is measured to 2.56MΩ and second is 0.9Ω. Can anybody tell me if it is ok or not and what these values should be?
I also measured the resistors given by FrenchMike and the 4.7KΩ ones are ok but the 47KΩ one is measured to 37.8KΩ in my case.
It would be nice to be able to fix it.

Regards
Fegyvej
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=10538&d=1318447572

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=10539&d=1318447584

[FrenchMike]

Hi,
I have bought a Rover 75 in the summer and now in the first cold days I tested the FBH and it was just starting up and stopping after about 2 minutes. I could hear the fan and the water pump but no clicking noise from the fuel pump. I tested the fuel pump via giving +12V on it and then I could hear the clicking noise.
I searched the net and found this thread which seems to fit my problem, thanks to FrenchMike :}.
I removed the control circuit and removed the paste from it, then found the paste black above 2 resistors and one leg of the ELMOS. It looks like burned and I could see a very small amount of black thick liquid like thing when I removed the paste.
Unfortunatelly these resistors are different ones.
One is above and a bit left from the 47K one and the other is below and a bit right from the 47K one. The first is measured to 2.56MΩ and second is 0.9Ω. Can anybody tell me if it is ok or not and what these values should be?
I also measured the resistors given by FrenchMike and the 4.7KΩ ones are ok but the 47KΩ one is measured to 37.8KΩ in my case.
It would be nice to be able to fix it.

Regards
Fegyvej

Hi Janos,

your letter box is full ...

[cb750chris]

Hi, just to ressurect an old thread.
I am trying to get a FBH running on an MGZT. It is a retrofit unit (if that makes any difference)
I have installed the fuel pump that is needed, and this works (checked by supplying 12V to pin 6) of the heater.
The fault is that the fan runs for about 3 seconds, then pauses for about 4 seconds, then the fan runs for about 2 mins.

I have checked the 47K Ohm, and the 4.7K Ohm resistors (the 47 K Ohm meters up at 49.8 K Ohm, so should be ok?

The other things I have checked are that, on initial start up, the glow plug gets a puse of power, but then no more power is supplied. There is no drive sent to the fuel pump.
I have tried swapping the PCB with a friend, and the problem follows the PCB (suggesting the car "services" are ok, it is the PCB that is faulty)

There is a "suspicious" looking surface finish on the item that fegyvej highlighted (in post #63), next to the 47KOhm resistor. This item looks corroded / burned. This item goes between a power pin, and pin 6(?) of the elmos device (counting clockwise from the 1/2 moon orientation marker)

Any suggestions where to look next?

Thanks
Chris

[FrenchMike]

Hi, just to ressurect an old thread.
I am trying to get a FBH running on an MGZT. It is a retrofit unit (if that makes any difference)
I have installed the fuel pump that is needed, and this works (checked by supplying 12V to pin 6) of the heater.
The fault is that the fan runs for about 3 seconds, then pauses for about 4 seconds, then the fan runs for about 2 mins.

I have checked the 47K Ohm, and the 4.7K Ohm resistors (the 47 K Ohm meters up at 49.8 K Ohm, so should be ok?

The other things I have checked are that, on initial start up, the glow plug gets a puse of power, but then no more power is supplied. There is no drive sent to the fuel pump.
I have tried swapping the PCB with a friend, and the problem follows the PCB (suggesting the car "services" are ok, it is the PCB that is faulty)

There is a "suspicious" looking surface finish on the item that fegyvej highlighted (in post #63), next to the 47KOhm resistor. This item looks corroded / burned. This item goes between a power pin, and pin 6(?) of the elmos device (counting clockwise from the 1/2 moon orientation marker)

Any suggestions where to look next?

Thanks
Chris

Hi,the first component is a capacitor and the second a one ohm resistor.

If you have checked all the resistors,remains the Elmos component..:shrug:

Mike

[dj_lyw]

Hello everyone! I have a picture with my FBH and I tested all resistors under that troublesome glued paste and everything ok, except of a green electronic piece that my multimeter read infinite. It looks like a resistor but nothing wrote on it(if it's a capacitor pls tell me what is the value). I will attach a picture with that component and pls tell me what it is(that circled and it is on pin 6 of ELMOS 10026B). Thanks in advance!

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=17124&d=1350591242

[Rbro188]

This is the answer to all the Fbh funny faults, have fixed my own car first and add the manual over ride Runs perfect. Then fitted a faulty unit to my wife's car, carried out this repair to it and away it went as well heats up perfect
Thank you very much mike u the man, Two more warm humans thanks to you

Richard and Clare Brown:bowdown:

[Vexatus]

@dj_lyw, I can't see nothing marked green you the pic you've posted, but the one in red circle is a 4k7 resistor. It was also damaged on my PCB and just replaced it.

I'd also like to say hello to everyone, it's my first post here - I've just found this forum today and it contains the largest ammount of data on fixing Webasto PCB's.

I have WEBATO Thermo TOP Z/C-D mounted in my BMW E46 but actually the board and the FBH it self is exactly the same as the one from your Rovers. In my car it only works as an aditional heater, when engine runs. However it's possible to reprogram it to work as a parking heater (using BMW INPA or BMW DIS diagnosis apps).
But in order to do that I need to make it work... Which is a problem :(

I had 2 errors in both BMW INPA and in WEBASTO ThermoTest:
1. K-bus break
2. water pump circuit break

As I wrote above I've changed the broken resistor today and the first one disapeared. So I tried to connect the water pump straight to the +12V - not working :( So I've connected P21W bulb in it's place and started the engine... It is alive!!! My happienes didn't last long - now it's getting the k-bus error randomly.

Is it possible that 10026B is damaged and works only sometimes? Is the Melexis chip plug-n-play to this board?
If car ignition is turned off the errors shows straight away, when engine is working, it's random (perhapse this are only some communication errors on the k-bus?), but still stops the FBH.
However, in BMW, ising the INPA, there is an option for FBH with 2 settings: "k-bus" or "conventional". When is set to "k-bus" - PIN1 is inactive and device only works as additional heater. When changed to "conventional" then you can start it using PIN1 so actually I could disconnect k-bus cable (and use WEBASTO cable and ThermoTest) to diagnose it. I think this should prevent the k-bus error and I could start the FBH using timer, remote or antyhing else... and it's still driven by PIN5 (thermo switch).

BTW, does anyone know if it's possible to fix the water pump? I've heard it's a brushless motor in there...

Best regards from snowy Poland (it's -2 outside and will be -20 soon so FBH is a great thing)
Greg

[Vexatus]

Hi again,

a little upadte on this one. the k-bus breakdown error comes up when the unit is suppose to start the normal heating mode. So here what happens:
- the device starts up, the air fan is working at about 90%, the glow plug is heating
- it start to pump a fuel for some time and the air fan is runing at about 20%

And this is the end, at this point the air fan stops for a momment, the ThermoTest connection breaks and after a momment it start the air fan again and the FBH status is "cooling". Also the k-bus breakdown errors comes up at this momment. When I've connected to the car via diagnosis software (BMW INPA), at the momment when the fan stops for few seconds the device status was "fan interrupt" (this I couldn't see in ThermoTest as the connection was breaking).
All the time I'm emulating the water pump with P21W bulb.

Any ideas?

I'll take the PCB out again today and recheck resistor again. Also, it happened once that the FBH started and run for a whole cycle (the water pump error is there all the time and it wasn't emulated at this time). So I adume this must be the PCB faulty. But can resistor cause this ot rahter it's the k-bus IC?

Looking forward
Greg

[FrenchMike]

Hi again,

a little upadte on this one. the k-bus breakdown error comes up when the unit is suppose to start the normal heating mode. So here what happens:
- the device starts up, the air fan is working at about 90%, the glow plug is heating
- it start to pump a fuel for some time and the air fan is runing at about 20%

And this is the end, at this point the air fan stops for a momment, the ThermoTest connection breaks and after a momment it start the air fan again and the FBH status is "cooling". Also the k-bus breakdown errors comes up at this momment. When I've connected to the car via diagnosis software (BMW INPA), at the momment when the fan stops for few seconds the device status was "fan interrupt" (this I couldn't see in ThermoTest as the connection was breaking).
All the time I'm emulating the water pump with P21W bulb.

Any ideas?

I'll take the PCB out again today and recheck resistor again. Also, it happened once that the FBH started and run for a whole cycle (the water pump error is there all the time and it wasn't emulated at this time). So I adume this must be the PCB faulty. But can resistor cause this ot rahter it's the k-bus IC?

Looking forward
Greg

Hi,

Looks like a flame out to me:

17414
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=17414&d=1351681714

And a water pump error is produced by open circuit OR short circuit.

Replace it by a bulb for test ...

Mike

[Vexatus]

Hi Mike,

yes, I'm "emluating" the pump with the bulb to even start the FBH. And, as I wrote, it's starting.
What can be a cause of "flame out"? Flame detector deffect?
And can the "flame out" error trigger the "k-bus breakdown" error?

[FrenchMike]

Hi Mike,

yes, I'm "emluating" the pump with the bulb to even start the FBH. And, as I wrote, it's starting.
What can be a cause of "flame out"? Flame detector deffect?
And can the "flame out" error trigger the "k-bus breakdown" error?

Lot of things can produce an error;particularly for safety,the glow plug
resistor is constantly sampled;
if it falls under 0.6 ohms or so ,a burn out sequence is started...

Have a look at my diagnostics timings .

[Vexatus]

Yes, I can see that glow plug started to dropp and then the flame detecotr showed null (means that FBH stopped to burn) - this is what I can understand from that...
Unfortunatelly I'm unable to save my graphs because, as I wrote before, at the momment when it happens the "k-bus breakdown" error shows up and it's disconnecting the ThermoTest app. Also it's the only error that appears. Just came to my mind that perhapse FBH is sending it's internall error and car's diagnostic system can't understnd it so it's showing the error. I'll try to disconnect the k-bus or recode the FBH operating mode from k-bus to conventional. Perhapse then I'll be able to catch the real error or the graphs at least...
But first I'll take the control unit out again and recheck all the resistors.
Would the device even communicate with the car if the k-bus chip was broken?

Best regards
Greg

[FrenchMike]

Yes, I can see that glow plug started to dropp and then the flame detecotr showed null (means that FBH stopped to burn) - this is what I can understand from that...
Unfortunatelly I'm unable to save my graphs because, as I wrote before, at the momment when it happens the "k-bus breakdown" error shows up and it's disconnecting the ThermoTest app. Also it's the only error that appears. Just came to my mind that perhapse FBH is sending it's internall error and car's diagnostic system can't understnd it so it's showing the error. I'll try to disconnect the k-bus or recode the FBH operating mode from k-bus to conventional. Perhapse then I'll be able to catch the real error or the graphs at least...
But first I'll take the control unit out again and recheck all the resistors.
Would the device even communicate with the car if the k-bus chip was broken?

Best regards
Greg

No, Search for Melexis TH3122 (same)

[Vexatus]

Ok, so if all resistors are fine, I'll change the TH3122 (only supplier I've found is Mr Resler) so by the time I'll have it, my water pump should be fixed/changed to a new one.

Then you Mike, I'll let know if any updates :)

BTW, have you been ever disassambling this water pump? It's PIERBURG and I've heared that there is brushles motor inside... BOSH pumps are having normal DC motors where you can change brushes, but I have no idea what about this one?

[FrenchMike]

Ok, so if all resistors are fine, I'll change the TH3122 (only supplier I've found is Mr Resler) so by the time I'll have it, my water pump should be fixed/changed to a new one.

Then you Mike, I'll let know if any updates :)

BTW, have you been ever disassambling this water pump? It's PIERBURG and I've heared that there is brushles motor inside... BOSH pumps are having normal DC motors where you can change brushes, but I have no idea what about this one?

Sorry,i never dismantled one !
but electrically speaking it acts as a classical DC motor ...

Good luck

Mike

[Vexatus]

Hi again...

Actually I think it's built like the PC fan inside... I mean the electronics ;) But I'll let know when I'll disassable it :)

However, I heva the PCB on my desk again and from this photo:
http://lh6.ggpht.com/_iIFYxIPjiKY/TRoIpg0hVQI/AAAAAAAABzU/VaYR65R3lMg/28122010554.JPG
source: http://www.the75andztclub.co.uk/forum/showpost.php?p=641338&postcount=9
A - was fried and looks like a capacitor to me (it's between k-bus line and circuit ground so I'd say it's the k-bus filtering) and according to the TH3122 datasheet it should be 82-100pF - can anyone please confrm?
C - shows about 2 Ohm on my multimeter - can you please confirm?
Evetyhing else looks fine. I'm going to search for the capacitor and if it won't help... Then I nees to order TH3122... So few weeks to take the FHB out from the car, clean everything and fix the pump...

Thanks in advance!
Greg

[Vexatus]

Hi Mike,

according to the TH3122 datasheet (page 6, figure 8) A=100pF.
Here is the datasheet:
http://www.yeint.ru/suppliers/melexis/pdf/TH3122_004.pdf
Also there is a 10R resistor as a "protection", however in table on page 9 you can see k-bus limit Ilim=100mA. So if I'm reading it correctly then something arround 150R in the k-bus line should limit the current to little bellow 100mA. What do you think?

Best regards
Greg

[FrenchMike]

Hi Mike,

according to the TH3122 datasheet (page 6, figure 8) A=100pF.
Here is the datasheet:
http://www.yeint.ru/suppliers/melexis/pdf/TH3122_004.pdf
Also there is a 10R resistor as a "protection", however in table on page 9 you can see k-bus limit Ilim=100mA. So if I'm reading it correctly then something arround 150R in the k-bus line should limit the current to little bellow 100mA. What do you think?

Best regards
Greg

Hi Greg,

Not sure it's allowed ,slew rate could be seriously disturbed .

Simplest way is disconnection !

Mike

[Vexatus]

Well, I think this would be an option:
http://www.freescale.com/files/microcontrollers/doc/app_note/AN2342.pdf
Figure 5.

Unfortunatelly disconnecting in bimma is not an option :( It's locking the device and you can't do anything with it... Can't unlock using ThermoTest so it must remain connected to the car :/

Best regards
Greg

P.S. I'm ordering the TH3122 - it's last hope to make it work...

[FrenchMike]

Well, I think this would be an option:
http://www.freescale.com/files/microcontrollers/doc/app_note/AN2342.pdf
Figure 5.

Unfortunatelly disconnecting in bimma is not an option :( It's locking the device and you can't do anything with it... Can't unlock using ThermoTest so it must remain connected to the car :/

Best regards
Greg

P.S. I'm ordering the TH3122 - it's last hope to make it work...

OK,you have the BMW config,then you can without risk insert a protective
resistor of several kohms.

I guess you know how to remove the IC ..

Mike

[Vexatus]

Won't this disturb the dialog between FBH and car?

Yeap, I can handle changing the IC ;)

Thank you
Greg

[FrenchMike]

Won't this disturb the dialog between FBH and car?



Possible,begin with a high value then decrease if prob.

The main cause of killing the IC is leaving the 6 pins connector in place
WITHOUT power on the 2 pins one.

good luck.

Mike

[Vexatus]

1k would limit it to no more then 14,5 mA.

However - I've disassabled the pump and it's BLDC... Do you have an idea about type of transistor in the WEBASTO board? I'm mean the power transistors driving pumps, fan etc.? The same thing is in the pump and would need any data to see if it's working and if driving transistors are working.
I'll post some photos of it when it's cleaned better ;)

Best regards
Greg

[FrenchMike]

1k would limit it to no more then 14,5 mA.

However - I've disassabled the pump and it's BLDC... Do you have an idea about type of transistor in the WEBASTO board? I'm mean the power transistors driving pumps, fan etc.? The same thing is in the pump and would need any data to see if it's working and if driving transistors are working.
I'll post some photos of it when it's cleaned better ;)

Best regards
Greg

They are very robust !

BTS 141 smart power switch

[Vexatus]

Thank you Mike :) Well, something's wrong with board in my pump - perhapse one of the driving transistors or just a cold joint - we'll see... The entire circuit is in something that looks like the PU foam so I can only clean it mechanically. Some of the elements fell of the board whil cleanig, so I'll solder it back tomorrow and check if there's something damaged. Actually only half od the circuit is broken. It happens offen in PC fans - the motor has 4 idle positions and it's starting from two of them, in 2 - it won't start...

[Vexatus]

Ok, theoretically PCB is fixed. Old IC was removed:
http://mydlarz.info/galeries/bmw/e46/webasto/controller/no_chip.JPG
and the new one
http://mydlarz.info/galeries/bmw/e46/webasto/controller/chips.JPG
was soldered in place :)
http://mydlarz.info/galeries/bmw/e46/webasto/controller/new_chip.JPG
You can see it covered with liquid colophony to prevent oxidation.

Haven't got time to test it yet ad my FBH is in home so I need to put it back to the car.

Also I've made a progress with water pump. I'm not sure if there's the same pump in Rover but in my BMW there is a Pierburg BLDC pump. I had to destroy the back cover on it at it was all filled with something looking like PU foam. I don't know an easy way to remove PU foam so it took me about 6 hours of machanically removing it with screwdriver and other hand tools :shrug: Few elements fell of during this process but it wasn't an issue :)
http://mydlarz.info/galeries/bmw/e46/webasto/pump/PUMP_fixed.JPG
Ok - I've soldered those resistors back and also transistor 1 and resistor 2 were loose - looks like cold joints were an issue, just like I thought. Those BLDC's are hard to broke ;) This was also covered with colophony and will be filled with silicone to prevent humidity destroing it.

Now the pump is working just like it should and waiting to be mounted back in the car with rest of the FBH. Finally :)

Again - thank you Mike for your help and I will let know soon if the FBH is working now... should be early next week :)

[FrenchMike]

Ok, theoretically PCB is fixed. Old IC was removed:
http://mydlarz.info/galeries/bmw/e46/webasto/controller/no_chip.JPG
and the new one
http://mydlarz.info/galeries/bmw/e46/webasto/controller/chips.JPG
was soldered in place :)
http://mydlarz.info/galeries/bmw/e46/webasto/controller/new_chip.JPG
You can see it covered with liquid colophony to prevent oxidation.

Haven't got time to test it yet ad my FBH is in home so I need to put it back to the car.

Also I've made a progress with water pump. I'm not sure if there's the same pump in Rover but in my BMW there is a Pierburg BLDC pump. I had to destroy the back cover on it at it was all filled with something looking like PU foam. I don't know an easy way to remove PU foam so it took me about 6 hours of machanically removing it with screwdriver and other hand tools :shrug: Few elements fell of during this process but it wasn't an issue :)
http://mydlarz.info/galeries/bmw/e46/webasto/pump/PUMP_fixed.JPG
Ok - I've soldered those resistors back and also transistor 1 and resistor 2 were loose - looks like cold joints were an issue, just like I thought. Those BLDC's are hard to broke ;) This was also covered with colophony and will be filled with silicone to prevent humidity destroing it.

Now the pump is working just like it should and waiting to be mounted back in the car with rest of the FBH. Finally :)

Again - thank you Mike for your help and I will let know soon if the FBH is working now... should be early next week :)

Well done !

For your tests,in order to firstly rule the pump out,replace it simply by a 21w bulb....

Good luck

Mike

[Onepinshort]

Hi guys

I would like to start by thanking FrenchMike for all valuable info and for sharing his knowledge:)

As of myself I am working on two Webasto heaters from E39 BMWs.

Heater 1: Combustion fan running at full speed. Have found one broken resistor on the circuit board. Will the heater work if a swap the broken resistor with a new one or might the k-bus/th3122 be broken as well?

Heater 2: Totally dead when applying power to pin 1. All the resistors on the circuit board are fine. Question, will the heater work if I swap the k-bus/Th3122 with a new one?

Anxious for an answer.

//Andreas in Sweden

[Vexatus]

Hi and welcome,

Heater 1: Combustion fan running at full speed. Have found one broken resistor on the circuit board. Will the heater work if a swap the broken resistor with a new one or might the k-bus/th3122 be broken as well?

I assume that after some time it just stops? Can you hear water pump or fuel pump runing as well? Tehere's no answer to your question - you need to replace the faulty element, put the control unit back in to the FBH and test it. If it works then you're fine. If no - well, you know what to do.

Heater 2: Totally dead when applying power to pin 1. All the resistors on the circuit board are fine. Question, will the heater work if I swap the k-bus/Th3122 with a new one?

Anxious for an answer.

//Andreas in Sweden
Ok, this is the interesting part. You need to know then in bimmas the FBH had two options:
1. additionl heater - supporting engine heat up when started cold (bellow 7*C outside)
2. parking heater - able to run when engine is turned off.

If your's was installed as option #1 then it won't respond to voltage on PIN1. You need to recode it (with BMW DIS - it's the easiest way).

In E46 the parking heater was driven by auxiliary clock (the small thing with display and WEBASTO logo on it). But AFAIK in E39 it was controlled by MID or instrument cluster if you had the full OBC.

Best regards
Greg

[Onepinshort]

Quote:
Originally Posted by Onepinshort http://www.the75andztclub.co.uk/forum/images/buttons/viewpost.gif (http://www.the75andztclub.co.uk/forum/showthread.php?p=1201188#post1201188)
Heater 1: Combustion fan running at full speed. Have found one broken resistor on the circuit board. Will the heater work if a swap the broken resistor with a new one or might the k-bus/th3122 be broken as well?

I assume that after some time it just stops? Can you hear water pump or fuel pump runing as well? Tehere's no answer to your question - you need to replace the faulty element, put the control unit back in to the FBH and test it. If it works then you're fine. If no - well, you know what to do.

Quote:
Originally Posted by Onepinshort http://www.the75andztclub.co.uk/forum/images/buttons/viewpost.gif (http://www.the75andztclub.co.uk/forum/showthread.php?p=1201188#post1201188)
Heater 2: Totally dead when applying power to pin 1. All the resistors on the circuit board are fine. Question, will the heater work if I swap the k-bus/Th3122 with a new one?

Anxious for an answer.

//Andreas in Sweden

Ok, this is the interesting part. You need to know then in bimmas the FBH had two options:
1. additionl heater - supporting engine heat up when started cold (bellow 7*C outside)
2. parking heater - able to run when engine is turned off.

If your's was installed as option #1 then it won't respond to voltage on PIN1. You need to recode it (with BMW DIS - it's the easiest way).

In E46 the parking heater was driven by auxiliary clock (the small thing with display and WEBASTO logo on it). But AFAIK in E39 it was controlled by MID or instrument cluster if you had the full OBC.

Best regards
Greg

Hi and thanks for a fast answer Greg. I have the additional heater in my car.

[Vexatus]

In this case it won't work if you apply 12V on PIN1. You need to recode the FBH. You can do it using DIS or NCS expert. You'll find a lot of "how to's" on the internet. In the BMW the FBH is driven by k-bus. Also computer diagnostic would be good idea. You can build the webasto interfce (I've posted a link to a very simple interface earlier in this topic) and the webasto thermotest app is free to donwload from webasto web page.

Best regards
Greg

[jaki]

Hello,

Sorry, that I'm only a BMW driver but it seems that this thread is the best in Webasto repairing.
So: I have Thermotop C in my E61 diesel (original from factory so replacing pcb is not available as a spare part) and I have figured out that the problem is in fuel pump circuit (analysing s/w says the same). Ok, possible other fails also, but let's start from this.
The pump itself clicks when powered directly 12v an actually I managed once hear steady clicking form under my car, and a couple of times one or two licks. naturally the unit locks itself after three attemps, but fortunately I have BMW DIS analysinf s/w to unlock it.
I put multimeter to pump socket (near to pump) and started the unit with remote control. Voltage rose from 0 to 0,78 V and it looks like its ticking (I have analog display as well).
My conclusion: fuel pump electronic circuit is broken, and I guess it is the end stage (read fet or transistor). Am I in the right direction? And any idea what component (and type) it is is inte circuit board?
Im an electrical engineer and soldering iron is quite familiar tool to me :}

[FrenchMike]

Hello,

Sorry, that I'm only a BMW driver but it seems that this thread is the best in Webasto repairing.
So: I have Thermotop C in my E61 diesel (original from factory so replacing pcb is not available as a spare part) and I have figured out that the problem is in fuel pump circuit (analysing s/w says the same). Ok, possible other fails also, but let's start from this.
The pump itself clicks when powered directly 12v an actually I managed once hear steady clicking form under my car, and a couple of times one or two licks. naturally the unit locks itself after three attemps, but fortunately I have BMW DIS analysinf s/w to unlock it.
I put multimeter to pump socket (near to pump) and started the unit with remote control. Voltage rose from 0 to 0,78 V and it looks like its ticking (I have analog display as well).
My conclusion: fuel pump electronic circuit is broken, and I guess it is the end stage (read fet or transistor). Am I in the right direction? And any idea what component (and type) it is is inte circuit board?
Im an electricar engineer and soldering iron is quite familiar tool to me :}

Hi,

Voltmeter is useless;put a scope on pin 6 and you'll see positives pulses
40 ms wide at a rate of 1 to 2.3 per sec.
In case of no pulse,there are lots of cause possible to prevent feeding fuel
(for safety reasons).
The end stages Mospower are very robust ..check resistors firstly..:}

Mike

[jaki]

Hi,

Voltmeter is useless;put a scope on pin 6 and you'll see positives pulses
40 ms wide at a rate of 1 to 2.3 per sec.
In case of no pulse,there are lots of cause possible to prevent feeding fuel
(for safety reasons).
The end stages Mospower are very robust ..check resistors firstly..:}

Mike

Thank's for fast reply. Ok, the pulse width is so narrow. I still think my high quality multimeter should have indicated this with it's analog bar, but not sure anymore. Unfortunately I don't have scope in my hand, thinking to buy one. I will once more come back to pump itself and test it with "manual" pulsing. If it still clicks, then I remove and look at the pcb. resistors does not sound very easy to replace.
If I don't see anything clear what is burn/broken I will rise my hands up. Fortunately we have here in Finland also a repair shop special for these Webasto pcb's from BMW and others.
I will report when I have studied a bit more.

[jaki]

Ok, I give up, I surrender :mad:
I removed PCB, I couldn't find anything suspicious there, measured every resistor (I think) and those seemed to be ok.
I studied a bit fuel pump circuit and it seems that pump is driven by one IC with 8 legs and it is soldered also from its body to board. I cheked that +12V circuit is ok to chip and signal from chip to pin 6 in X1 is ok also. I cannot do anything more.
Frenchmike, still repairing these? Aprog delivery time today?

[jaki]

No answer, so my one man talking continues...:)
The chip is actually 10 leg VND05BSP monolitic dual channel switch from SGS Thomson. One channel is only used.

I'm not sure, but if I understood correctly the chip schematic, it will jump from 0 to 12V when input roses from 1,5V or less to 3,5V or more. So, when in my case, output voltage is about steady 0,8V when switched on, I'm quite positive that this chip is the guilty. I'm I right?

[Vexatus]

Best way would be building a diagnostic cable. You'll have the answer. I think you've mentioned you have a BMW cable and DIS. Is it showing any errors? AFAIK the fuell pump is only driven by short +12V pulses. If it's not clicking, when FBH starts it can also mean any FBH error that prevents the device to start. I had my water pump broken and the melexis chip broken too. I never heared of any issues with fuell pump control. The pump itself is available and not very expensive too. I think that you should be able to find the fuell pump pinout on the internet and try to apply +12V manually to it's pin. It's driven from the pin6 of X1 conenctor in the FBH PCB.

Best regards
Greg

[jaki]

Best way would be building a diagnostic cable. You'll have the answer. I think you've mentioned you have a BMW cable and DIS. Is it showing any errors? AFAIK the fuell pump is only driven by short +12V pulses. If it's not clicking, when FBH starts it can also mean any FBH error that prevents the device to start. I had my water pump broken and the melexis chip broken too. I never heared of any issues with fuell pump control. The pump itself is available and not very expensive too. I think that you should be able to find the fuell pump pinout on the internet and try to apply +12V manually to it's pin. It's driven from the pin6 of X1 conenctor in the FBH PCB.

Yes, I can read and control FBH no problem with my s/w. Actually there have been several issues (discussed with specialists) about pump control in E6X BMW cars.
As written earlier, only error it gives is "fuel pump circuit open". I read VND05BSP manual, and it has diagnostic pin which, I assume it used in Webasto also. It is quite stupid and give only very basic type error situations.
When its gives that previous mentioned error message, there are actually few possibilities:
1. pump circuit really is open (not in my case, all the cables and pump are ok)
2. the chip is partially dead but manages to send this circuit message to main cpu
3. chip is totally dead and main cpu assumes that fuel circuit is open.

But, remember that when I start FBH, I can read small voltage from pump connector, meaning that this chip cannot be totally dead! When Webasto is shut down, this small voltage drops to 0.
Please read ALL of my previous posts.
Unfortunately none told me (or they didn't know) resolutions for those.
In E60 the fuel pump seems to be quite rigid, and so mine is clicking as it should be. You can manually test it, but not run (read, 40 ms pulses in 1 to 2 Hz)

[COLVERT]

Ok, I give up, I surrender :mad:
I removed PCB, I couldn't find anything suspicious there, measured every resistor (I think) and those seemed to be ok.
I studied a bit fuel pump circuit and it seems that pump is driven by one IC with 8 legs and it is soldered also from its body to board. I cheked that +12V circuit is ok to chip and signal from chip to pin 6 in X1 is ok also. I cannot do anything more.
Frenchmike, still repairing these? Aprog delivery time today?

Send FrenchMike a PM. ( Private message. ) You will get a much faster reply if you do. :D:D

Click on his name, up on the left, and then click on 'Send private message'.



Colvert.

[jaki]

Send FrenchMike a PM. ( Private message. ) You will get a much faster reply if you do.

Actually I allready did some time ago. Unfortunately, my model is new to him. But: as soon I get better from my flu, I install my modificated pcb, and test it. If it does not work, I change the chip and if it is still without pump current, I will give it to local expert (they have huge repair queue presently). Our cold days will last about one month still, so I should repair it relatively quick or it does not matter anymore for this winter :}

Edit: I swapped output to an other FET port in that circuit. Didn't help. Cuircuitry worked exatrly in a same way than before (so, I didn't break anything extra ;) )Ok, it was too difficult job to me and my tools anyway (too small connections). So it is possible that my connection was wrong soldered. I ordered new chip and will have it in a couple of days. Local electronic shop can do the swapping without a problem. I will then once again check all the cables & connections, put everything together...and hope the best. If it does not work, I will give it to expert.

[Vexatus]

jaki, if you'll apply a lot of flux or colophony then solder will hold to the copper and "get away" it self from the laminate.

Best regards
Greg

[HarryM1BYT]

Thank's for fast reply. Ok, the pulse width is so narrow. I still think my high quality multimeter should have indicated this with it's analog bar, but not sure anymore. Unfortunately I don't have scope in my hand, thinking to buy one. I will once more come back to pump itself and test it with "manual" pulsing. If it still clicks, then I remove and look at the pcb. resistors does not sound very easy to replace.
If I don't see anything clear what is burn/broken I will rise my hands up. Fortunately we have here in Finland also a repair shop special for these Webasto pcb's from BMW and others.
I will report when I have studied a bit more.

In the absence of a 'scope, a logic probe with a cmos setting would pick up and show the pulses.

[dotsie]

A big thanks to Frenchmike for fixing 2 pcb's for me.Both FBH's are now running well.The man is a genius :)

[jaki]

A big thanks to Frenchmike for fixing 2 pcb's for me.Both FBH's are now running well.The man is a genius :)

Good for You, I even swapped (or electronic shop did it) new output stage for fuel pump, but result was same than before. I cheked fuel pump cabeling once again but everything was ok.
I found from motor-talk a couple gus with similar eerror codes. No answer there either :(
I give it up. I will visit an expert when I hve little more time.

[jaki]

Sad story to my Webasto.
I had problem with my battery (original from year 2004), and there was also litlle contact problems with battery cabling.
I managed fire my car with jump start and bought new battery. Everything else is ok, except this FBH. First: I couldn't get contact to it with my DIS. Then I realise that its fuse was blown. I replaced it and the I heard aux water pump running on all the time. Ahd: this is serious: I couln't still get any contact to it :( Even when car totally switched off water pump remains on, meaning I was forced t oremove that fuse.
So my unit seems to be very sick.

[David Lawrence]

Hi Greg,

I can confirm:
A :ceramic capacitor unknown value.
B:49.9k resistor
C:1 ohm resistor
D:4.7k resistor
E:ceramic capacitor unknown value.

Mike


Hi Mike,

Any idea which component causes the error message "Glowpin flame sense interrupted- Short circuit". I found one 4.7K resistor open circuit, but the error is still there. The glowpin is not short circuit because i tested it in another heater.

[FrenchMike]

Hi Mike,

Any idea which component causes the error message "Glowpin flame sense interrupted- Short circuit". I found one 4.7K resistor open circuit, but the error is still there. The glowpin is not short circuit because i tested it in another heater.

Hi,

The quickest way is checking all the resistors...

[David Lawrence]

Hi,

The quickest way is checking all the resistors...



It was a solder joint this time. It seems the chewing gum has attacked the joints on the resistors which was very confusing because when measuring the resistors on the top of their caps they read fine, but when I scraped away the varnish on the pads and measured there, they read open circuit. Ended up replacing 2 x 4.7K resistors and 1 x 10K one.


That chewing gum has a lot to answer for.

[FrenchMike]

It was a solder joint this time. It seems the chewing gum has attacked the joints on the resistors which was very confusing because when measuring the resistors on the top of their caps they read fine, but when I scraped away the varnish on the pads and measured there, they read open circuit. Ended up replacing 2 x 4.7K resistors and 1 x 10K one.


That chewing gum has a lot to answer for.

Yes,chewing gum + temperature :shrug:

[stevejspm]

I would like to offer my sincerest thanks & gratitude to FRENCHMIKE for sharing his knowledge on fixing the Webasto. I have a BMW X5 & as a result of following his diagnosis & repair procedure I successfully repaired mine today.

Well done FRENCHMIKE & a big round of applause to you! Thank you so much.

[FrenchMike]

I would like to offer my sincerest thanks & gratitude to FRENCHMIKE for sharing his knowledge on fixing the Webasto. I have a BMW X5 & as a result of following his diagnosis & repair procedure I successfully repaired mine today.

Well done FRENCHMIKE & a big round of applause to you! Thank you so much.

Very happy for you Steve and glad saving
all these condamned webasto's...:xmas-smiley-032:

Mike

[mashby]

MY STORY:

I came upon this Forum 3 years ago after my in tank fuel pump broke.
I found advice here to have my pump quickly and cheaply repaired.

I too also had the strange Fuel Burning Heater (FBH) behaviour caused by the K bus.
(Which I have since disconnected.)

As a regular reader, I have noted lots of threads about FBH issues and in particular
that the PCB was reported as being non repairable.

The cold days made me inclined to study the question. I began by trying to collect information about the circuit diagram etc, (not very easy)

At first I thought the Interface IC bus was the culprit.
I ordered the genuine interface IC bus (ELMOS 10026B) from Hong-Kong,
but one month later, nothing ;they forgot to ship
Meantime, I bought the Riesler interface Bus describe by Keith Alexander .
I discovered than his Interface Bus IC was a (Melexis TH3122) similar
and more easy to get.

Next, I built up a test bench and established communication between my laptop and
the Webasto PCB.
However, there was a combustion air fan error. (running at max speed).
Tracing the PCB ‘tracks’, I discovered than the power Mosfet’driver was always
ON although the Micro bus line concerned was live .The link is in fact a SMD (surface mounted) resistor well hidden under a kind of sticky sealant (looks like meringue.)
The resistor was marked 4.75 kOhms but my multimeter showed infinite !
Strange ,I had rarely seen that before in my professional live.

Anyway, I quickly replaced it and …..everything worked …..

I opened a new thread on the forums to tell the news.

So, the only possible cause, was that the resistors were being attacked by a chemical agent from that paste (meringue).

(can you imagine how many Webastos this may have affected all over the world !!)

I would like to freely publicise this valuable information, in the true spirit of the ‘Forum’ and it’s ethos of sharing information.

Most members will be able to do the work for themselves ( or know a man that can!).
However, I can do the repair for others who don’t feel like tackling the job themselves

TOOLS NEEDED:

Low power soldering iron with thin tip correctly earthed.
Table magnifier,
Solder
SM (surface mounted) resistors 4.7 Kohm ; 47Kohm


PROCEDURE

Extract the PCB from the FBH (5 screws)

Pic 1
http://rovermg1.free.fr/rovermg/thumbnails/dyMLhkJ5bQ16KPOGQCDM.jpg (http://rovermg1.free.fr/rovermg/images/dyMLhkJ5bQ16KPOGQCDM.jpg)

Remove that sticky white paste and clean the area to show the resistors.
Take a measurement of them: two 4.75 Kohm and one 47 Kohm.


Pic2

http://rovermg1.free.fr/rovermg/thumbnails/wiwCm4tc4g92bR3csgOk.jpg (http://rovermg1.free.fr/rovermg/images/wiwCm4tc4g92bR3csgOk.jpg)

If possible, built a test bench for checking out all the parameters before fitting on car.

Pic3

http://rovermg1.free.fr/rovermg/thumbnails/KyhACYUcOq1bfDSs8yx8.jpg (http://rovermg1.free.fr/rovermg/images/KyhACYUcOq1bfDSs8yx8.jpg)

Results

Pic4

http://rovermg1.free.fr/rovermg/thumbnails/mf7tiuGjTfi7LvgLmvvt.jpg (http://rovermg1.free.fr/rovermg/images/mf7tiuGjTfi7LvgLmvvt.jpg)

Enjoy your warmer car :):lol:

Mike
Mike,

I have a 2005 E53 with a erratic running combustion fan motor. It will start OK run for about 2 minutes then run erratically & shut down with INPA message Fan interruption. Have read about faulty 4.7k resistors in PCB but could it be clogged combustion chamber causing flame out? Can you repair BMW PCD's. I am capable of changing resistors but don't want to start until sure that fault is PCB?

Would appreciate your thoughts

Mark A

[FrenchMike]

Hi Mark,

You have to know that i can't test entirely the BMW one's for the cycle is
depending on the Kbus 'car.

I only can test the driving of the external components .and read the recorded
errors.

The Rover's are more easy to test ..

However,i can still have a look :}

Mike

[cowmanmick]

my fbh wont fire up it runs but doesnt fire is it the pcb i would like french mike to have a look at it have anyone got a contact address for him ,or can mike please contact me himself,i would be apreciated for any help

[klarzy]

my fbh wont fire up it runs but doesnt fire is it the pcb i would like french mike to have a look at it have anyone got a contact address for him ,or can mike please contact me himself,i would be apreciated for any help

just click on his name and send him a PM....

[mashby]

Mike,

Do you still do PCB repairs?

[wolfdoguk]

Hi, and happy new year to everyone. My first post after being a member for ages, apart from P.Ming big russ and having him remap 2 ecu's. I don't really want to impose on the good people here, but I feel I need some answers from the boffins here! I have ploughed through endless threads and posts, but just got mesmerised, so I hope it's ok to post here!

I have a unhealthy obsession with fbh's, especially after reading the endless information on this site about them, and past experience with cab heaters in my trucks!
I have one already fitted to my saloon, but I bought one complete with pump, and retro- fitted it to my 52 plate tourer.
As soon as I put fuse 8 in, the fan motor burst into life and ran a few seconds. I couldn't get it to run at all after that, it was dead, tried resetting it by removing the fuse, but still nothing on earthing pin 6. I replaced the fuse a day or so later and it fired up and ran! I was a happy chappy! However, after a week it just started running the fan and the water pump, but it just wouldn't fire. I tried resetting again, but nothing.
I have a perfectly good one, which I know works on my 75 saloon, swapped them round, it did the same thing when connecting the battery to the saloon, only this time it burst into life, only to cut out and just run the fan, blowing cold air out of the exhaust and circulating water. Fired up the known good one on the tourer (originally off the saloon) and it worked perfectly!!..... For a week.... Now, Monday, that one has started the same game!! Although, this one doesn't start running on connecting the fuse, symptoms are the same, i.e. running the fan (a little faster than usual) and water pump, but not firing!I also bought 2 gsm's off ebay after reading all about them on here, but they aren't without their faults either!! one doesn't quite work as it should, although, i have no instructions apart from what's on the listing and what i can squeeze out of the guy by asking! and the other didn't work at all!!!!I also fitted the maplin relay on the heater
too, as done by another excellent life-saving-member, it was lovely while i had it all working "to a fashion"! Now, someone mentioned that they aren't very good as anchors or doorstops, but I'm liking the idea of donning my steel toe cap boots and launching them like rugby balls, or, a splash of petrol and a match to activate them....I hope the other genius aka FrenchMike reads this, because, surely it would be an unlikely coincidence that both pcb's fail, and in the same way in such a short time? unless it's something that is blowing the resistors, but there's only the 5c temp wire, dosing pump and pin 6 earth activator fitted, the k-bus is disconnected.On another note, i removed the first pcb, cleaned off the gum around the capacitors and found the furthest right one was black on where it had sat on the resistors I also took out the pcb for the other fbh, but surprisingly, this one is almost charred under the blob of gum,on the right of the pcb. Now, another God "HarryM1BYT" shows a picture of a different resistor marked as one of the" failers" to what FrenchMike shows in his picture, unless I'm looking at it wrong, but does anyone know what type the other resistors are and what size they are in that area on the board, under the blob? and what particular size they are, ohm, wattage and physical size etc, or doesn't it matter? if a reading can't be found with a multimeter (i just bought a new one, and both my old one and new one don't show any readings, as if they are open circuit, so how do we know what to replace them with?! i'm not a big electrical wizzard, in fact i've never tackled anything as small and fiddly as these resistors) I've just ordered a table magnifier in the hope of doing these myself....
Even "if", by some miracle I get them fixed, I'll still be worried about putting it back on the car in case it blows again!
I've attached a couple of pictures of the bought pcb (first one to snuff it) which seems to show one of the offending resistors looking suspect and the pcb from the known good one (well, was a good one...) Showing the charred area around the right hand capacitor where the gum was.
Any pointers and/ or ideas would be gratefully received.

Thank you very much!
Paul

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43796&d=1420692365
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43797&d=1420692397

[wolfdoguk]

Hi Paul,

it seems you get several issues ; you have to know for safety reasons a error
is produced in case of:

Battery voltage lower than 10.5 volts
-Glow plug open or short circuit
-Circulation pump open or short circuit
-Combustion fan open or short circuit
-Fuel pump open or short circuit
-PCB defective

Check separately each component.

43798


Never remove power (fuse or 2 pin plug) before removing the 6 pin connector.

For test at any temp , connect pin 3 to earth (NOT pin 6)

Good luck

Mike
Thanks for that Mike, much appreciated.
Yes, silly me, I meant to say pin 3 of the 6pin plug, I use this to activate it via the gsm.
I wouldn't think there would be anything wrong with the fan, pump and glowpin, as it would be a coincidence to have the same fault on two different burners, but of course it can't be ruled out, I would suspect the fuel pump wiring, but not too sure how to check it. The batteries on both cars are very healthy, showing over 12.5 volts.
I'll try your test when I get chance, thank you for that.
What would you advise on resistors there, as they look pretty fried on the second pcb?
Thank you very much.

Paul

[FrenchMike]

To test the external components ,You have all the infos on my schematic

And Forget the color of the resistors .the ohmmeter is the only way.


Mike

[wolfdoguk]

Thank you once again Mike! I'll do the tests at the weekend or before if I get chance.

Paul

[decebalus]

Hello comunity, big thanks to French Mike and the passion he shows for these cars and to everyone that contributes to this forum, it's my second week here and i already found cheap solution to 2 of my problems, (how to get a cheap MAF sensor thanks to HarryM1BYT , and this one with the damaged pcb which eventually i will get it done)

I have the old version of the Webasto on my car which is 66232C, i tested with +12V to pin 1 and the machine starts for 2 minutes and then gone. I haven't tested the external components but i heard the air fan running for the 2 minutes it did and i check the hose that goes in the engine while working and there was some action going on, nothing to say about the fuel pump...btw does the schematic you Mike drawn for testing external components is valid for the old Webasto also? And one more the order to remove the 2 wires connected to Webasto is 1st 6-pin plug and then 2-pin plug, and to reconnect you need first to connect the 2-pin wires and after the 6 plug am i right?

One thing i haven't done is to remove the pcb (i don't remember where the instructions threat is) , i did some pictures to it as it is and eventually i'll remove it and find someone capable of doing the job around here as i'm from Bucharest(Romania)


I need to find a way to test the plug and the fuel pump beside getting done the pcb and also please teach me to say thanks to users

All the best
Alex :new_year:

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43936&d=1421191039.
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43937&d=1421191056

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43938&d=1421191088

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43939&d=1421191106.
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=43940&d=1421191123

[FrenchMike]

Hello comunity, big thanks to French Mike and the passion he shows for these cars and to everyone that contributes to this forum, it's my second week here and i already found cheap solution to 2 of my problems, (how to get a cheap MAF sensor thanks to HarryM1BYT , and this one with the damaged pcb which eventually i will get it done)

I have the old version of the Webasto on my car which is 66232C, i tested with +12V to pin 1 and the machine starts for 2 minutes and then gone. I haven't tested the external components but i heard the air fan running for the 2 minutes it did and i check the hose that goes in the engine while working and there was some action going on, nothing to say about the fuel pump...btw does the schematic you Mike drawn for testing external components is valid for the old Webasto also? And one more the order to remove the 2 wires connected to Webasto is 1st 6-pin plug and then 2-pin plug, and to reconnect you need first to connect the 2-pin wires and after the 6 plug am i right?

One thing i haven't done is to remove the pcb (i don't remember where the instructions threat is) , i did some pictures to it as it is and eventually i'll remove it and find someone capable of doing the job around here as i'm from Bucharest(Romania)


I need to find a way to test the plug and the fuel pump beside getting done the pcb and also please teach me to say thanks to users

All the best
Alex :new_year:

Hi Alex,

On your type (first one) no kbus is fitted ,so no worry about the disconnecting
plug order ..
The schematic is the same except the auxiliary command.
(you have to connect pin3 to +12v )

This model is more robust than the other ,then faults vicious to find out .

Is the 5 volt generated ?

Mike

[decebalus]

Hi Alex,

On your type (first one) no kbus is fitted ,so no worry about the disconnecting
plug order ..
The schematic is the same except the auxiliary command.
(you have to connect pin3 to +12v )

This model is more robust than the other ,then faults vicious to find out .

Is the 5 volt generated ?

Mike

Hello Mike,

So the scheme from post 121 you drawn remains the same except connecting +12v to pin3, not ground to pin3 as for the newer model, correct?

(sorry my knowledge of the machine is a bit poor) how can i measure if the 5v is on? (i have a metter for that)

Can it be possible to fix it or it's a waste of time?
My car is going to 9 o'clock temp indicator in about 20 minutes more or less depending on the driving style, do you think the thermostat has something to do with that?

Kindly thanks for getting envolved

Alex

[FrenchMike]

Hello Mike,

So the scheme from post 121 you drawn remains the same except connecting +12v to pin3, not ground to pin3 as for the newer model, correct?

(sorry my knowledge of the machine is a bit poor) how can i measure if the 5v is on? (i have a metter for that)

Can it be possible to fix it or it's a waste of time?
My car is going to 9 o'clock temp indicator in about 20 minutes more or less depending on the driving style, do you think the thermostat has something to do with that?

Kindly thanks for getting envolved

Alex

Hi Alex,

To read more accurately your engine temp,use the OBD in 7.0

http://www.the75andztclub.co.uk/forum/showthread.php?t=55585&highlight=board+diagnostics

You have a PM

Mike

[wolfdoguk]

To test the external components ,You have all the infos on my schematic

And Forget the color of the resistors .the ohmmeter is the only way.


Mike
Ok, I've been quite ill, so I only just got chance to do your tests Mike.
I took the worst pcb, the one that looked like the elmos was burned and experimented with it, it started giving me readings from all the resistors, so i re-soldered them, put it back in the car and it works again!
Now, while I was at it, I did your tests as per your schematic. On the water pump, the bulb lit, but not as bright as if going direct to the battery, and the pump made a noise, moving on, the combustion fan ran while the bulb was lit "half brightness" and the fuel pump lit up too, also not as bright. Does this sound ok?
The other boards have dead resistors on them, so I will change them and see what happens with them, although I'm not sure about the physical size of the smd resistors, I got 4k7 and 47k, the body size is 1206, but seems a little too big, would 0805 be better? and what wattage should they be, 0.25w or 0.1w?
Thank you!

Paul

[FrenchMike]

Ok, I've been quite ill, so I only just got chance to do your tests Mike.
I took the worst pcb, the one that looked like the elmos was burned and experimented with it, it started giving me readings from all the resistors, so i re-soldered them, put it back in the car and it works again!
Now, while I was at it, I did your tests as per your schematic. On the water pump, the bulb lit, but not as bright as if going direct to the battery, and the pump made a noise, moving on, the combustion fan ran while the bulb was lit "half brightness" and the fuel pump lit up too, also not as bright. Does this sound ok?
The other boards have dead resistors on them, so I will change them and see what happens with them, although I'm not sure about the physical size of the smd resistors, I got 4k7 and 47k, the body size is 1206, but seems a little too big, would 0805 be better? and what wattage should they be, 0.25w or 0.1w?
Thank you!

Paul

Yes Paul,everything is normal unless it will stop :}

http://rovermg1.free.fr/rovermg/images/ye9T6AdTxmWEgsi5xwo7.jpg


http://rovermg1.free.fr/rovermg/thumbnails/ye9T6AdTxmWEgsi5xwo7.jpg (http://rovermg1.free.fr/rovermg/images/ye9T6AdTxmWEgsi5xwo7.jpg)

And most of the resistors are 0805 /0.25 w

Mike

[sln8458]

Ok, I've been quite ill, so I only just got chance to do your tests Mike.
... On the water pump, the bulb lit, but not as bright as if going direct to the battery, and the pump made a noise, moving on, the combustion fan ran while the bulb was lit "half brightness" and the fuel pump lit up too, also not as bright. Does this sound ok?

Paul

Paul
Just a thought, the fuel pump is solenoid driven (it has a pulse signal) so the light should 'flash' in sync with the pump.
As mentioned in Mikes post #121
I think you could have a fuel pump issue, hence why both FBH's have issues when fitted to the car.

SteveN

[HarryM1BYT]

Paul
Just a thought, the fuel pump is solenoid driven (it has a pulse signal) so the light should 'flash' in sync with the pump.
As mentioned in Mikes post #121
I think you could have a fuel pump issue, hence why both FBH's have issues when fitted to the car.

SteveN

The easy way to know whether the pump is working, is to listen to it for clicks. The speed of the clicks vary, depending on the combustion state of the FBH, but they are easily heard. If its clicking you can be 99% sure it is pumping, but that doesn't guarantee fuel is coming out.

[FrenchMike]

The easy way to know whether the pump is working, is to listen to it for clicks. The speed of the clicks vary, depending on the combustion state of the FBH, but they are easily heard. If its clicking you can be 99% sure it is pumping, but that doesn't guarantee fuel is coming out.

Yes Harry and if fuel refuses to come ,a flame out error is generated and
the burner stops ...

:new_year:

Mike

[wolfdoguk]

Paul
Just a thought, the fuel pump is solenoid driven (it has a pulse signal) so the light should 'flash' in sync with the pump.
As mentioned in Mikes post #121
I think you could have a fuel pump issue, hence why both FBH's have issues when fitted to the car.

SteveN

Hi Steve,
Thanks for that, I was actually doing the light bulb test with the unit inactive, I wasn't 100% sure whether I was supposed to do it that way or not. However, after fiddling about with the pcb, I got it working again, and it's working now, although I've cut the wire from the temp sensor, so I only use it as a parking heater. I was concerned too about a pump issue, but I wondered if the wiring was shorting somewhere, as the previously mentioned pcb was very black, making me think it was completely shot because of a short or something, especially when the unit before stopped working too, and seeing that the only things wired externally of the fbh's, are the temp sender and the pump, or maybe it was a coincidence both units died?


The easy way to know whether the pump is working, is to listen to it for clicks. The speed of the clicks vary, depending on the combustion state of the FBH, but they are easily heard. If its clicking you can be 99% sure it is pumping, but that doesn't guarantee fuel is coming out.

Yes Harry, the pump is working, its clicking as the fbh wants it to, slowly at the start and getting faster as the fbh gets up to full speed and maintaining it until its switched off. When the car ate the burners, I tested the pump directly via the terminals, and it clicked as it should.


Thanks very much to everyone, especially Mike!

[HarryM1BYT]

Hi Steve,
Thanks for that, I was actually doing the light bulb test with the unit inactive, I wasn't 100% sure whether I was supposed to do it that way or not. However, after fiddling about with the pcb, I got it working again, and it's working now, although I've cut the wire from the temp sensor, so I only use it as a parking heater.

Fiddling about with it and it starting to work, might suggest it went into lockout....

If it tries to start three times in succession and fails to get ignition, it goes to lockout. It then remains locked out, until reset. You reset it by pulling the fuse or power plug, out briefly.

[wolfdoguk]

Fiddling about with it and it starting to work, might suggest it went into lockout....

If it tries to start three times in succession and fails to get ignition, it goes to lockout. It then remains locked out, until reset. You reset it by pulling the fuse or power plug, out briefly.
Yes, that was the problem to start with Harry, I thought it was in lockout and reset it so many times that I lost count. The other unit would start running as soon as power was applied, well, the fan started running at high speed for about a minute then stop, putting, grounding pin 3 would start the fan at high speed again along with the water punp, and stop after a couple of minutes. As you say, three times and it went into lockout, so I would reset, and the whole process would start again. K bus is disconnected. I traced back to problematic 4k7 resistor on that particular pcb.

[Spike05reg]

Hi Guys,
Hope you don't mid my asking, my 2005 year MG fbh hasn't worked since 2012. I dekoked it last week. The air fan was stuck and full of debris, and now it works if i give it 12v on pin 1, and successfully heats up the engine. Left to its own devices, nothing happens. The car's harness gives no signal on pin 1 regardless of the outside temp. Where should I look next please?
Mike.

[Snagger]

Hi Guys,
Hope you don't mid my asking, my 2005 year MG fbh hasn't worked since 2012. I dekoked it last week. The air fan was stuck and full of debris, and now it works if i give it 12v on pin 1, and successfully heats up the engine. Left to its own devices, nothing happens. The car's harness gives no signal on pin 1 regardless of the outside temp. Where should I look next please?
Mike.

If the unit is not starting at the correct temperature suspect faulty temp sensor, or wiring.

See 2nd and 3rd links in my signature.

Be aware if you need to change the temp sensor and you use the land rover ( L ) coded one from Rimmers, it will trigger the FBH at approx +10 deg or less, as opposed to the Rover oem one at +5deg or less.

Snagger.

[HarryM1BYT]

Hi Guys,
Hope you don't mid my asking, my 2005 year MG fbh hasn't worked since 2012. I dekoked it last week. The air fan was stuck and full of debris, and now it works if i give it 12v on pin 1, and successfully heats up the engine. Left to its own devices, nothing happens. The car's harness gives no signal on pin 1 regardless of the outside temp. Where should I look next please?
Mike.

Run signal is produced by the alternator being driven, it then goes to a thermostat behind the front bumper, set to close at or around +5C. So engine running and outdoor temperature needs to be below +5C before the FBH will run automatically.

Check my FBH Help by clicking the link below....

[bigbaldbloke]

Spike, if you don't mind me asking - did you "just" remove the top cover to sort the fan out?

Kev

[Spike05reg]

Many thanks Snagger and Harry. I'll go looking this weekend.
Kev, no, I stripped the whole shebang to dekoke it because I didn't know what I would find after a few years of inactivity. I couldn't see how the fan impellor came off, so I blew through the fan with compressed air, then ran it on 12v for a while shaking it to clear any dirt inside.
Thanks again,
Mike.

[Martin_J]

Thank you Mike for all your job you do here!

I am a newbie on this forum – found it recently. Thanks to this great discussion I could have discovered the same resistor problems on my Webasto PCB as well.

My Webasto had four problem resistors on the microprocessor side and one problem resistor on the flip side!

The Webasto however does not work yet. By mistake I have damaged part near processor and now I do not know what part is was.

Could someone possibly let me know the code marking which has been written on the part? I would try to replace it first and then carry on testing.

http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=44831&d=1423214604

Thanks a lot Martin

[FrenchMike]

Thank you Mike for all your job you do here!

I am a newbie on this forum – found it recently. Thanks to this great discussion I could have discovered the same resistor problems on my Webasto PCB as well.

My Webasto had four problem resistors on the microprocessor side and one problem resistor on the flip side!

The Webasto however does not work yet. By mistake I have damaged part near processor and now I do not know what part is was.

Could someone possibly let me know the code marking which has been written on the part? I would try to replace it first and then carry on testing.

Thanks a lot Martin

Hi Martin,

4751=4.75 kohm can be replaced by 4.7k (4701)
4992=49.9 kohm can be replaced by 47k (4702)

Good luck

Mike

[Martin_J]

Oh Mike, thanks a lot!
I am sorry. I was not very clear with my question. There is a part in the yellow square. See the new picture attached. It is a transistor, diode or some other part. I have damaged this part by mistake. Now I need to replace it.
Cay you look at the PCB if you can or someone else and read the the code which is written on the part so I can decode and substitute it?
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=44860&d=1423236162


Thanks a lot!
Martin

[FrenchMike]

Oh Mike, thanks a lot!
I am sorry. I was not very clear with my question. There is a part in the yellow square. See the new picture attached. It is a transistor, diode or some other part. I have damaged this part by mistake. Now I need to replace it.
Cay you look at the PCB if you can or someone else and read the the code which is written on the part so I can decode and substitute it?
Thanks a lot!
Martin

Something like "JE" if it can help :duh:

[vpug]

Hi

On my board its a A7w transistor, but my board is of a BMW so poss not the same.

Thanks vpug

Oh Mike, thanks a lot!
I am sorry. I was not very clear with my question. There is a part in the yellow square. See the new picture attached. It is a transistor, diode or some other part. I have damaged this part by mistake. Now I need to replace it.
Cay you look at the PCB if you can or someone else and read the the code which is written on the part so I can decode and substitute it?
Thanks a lot!
Martin

[vpug]

Something like "JE" if it can help :duh:

Hi Mike

I take it the IC's never got to you then, did you get any more yourself.

Thanks vpug

[FrenchMike]

Hi Mike

I take it the IC's never got to you then, did you get any more yourself.

Thanks vpug

Hi,

3 weeks ago i have send an order to the link you gave me ...
and on 26 of january i have received a message:

"Your Order has been shipped"

So fingers crossed :shrug:

Is your burner working ?

Mike

[pete 75]

Hi Mike,sent you a private email
Regards Pete

[vpug]

Hi Mike

Was that just the standard free post then not dhl like the one that I sent for ?
Last time they came in a week saying that the snail mail never got to you.
I never got the bmw webasto running as I pickup a c8 one and now have fitted that.

Thanks vpug

Hi,

3 weeks ago i have send an order to the link you gave me ...
and on 26 of january i have received a message:

"Your Order has been shipped"

So fingers crossed :shrug:

Is your burner working ?

Mike

[FrenchMike]

Hi Mike

Was that just the standard free post then not dhl like the one that I sent for ?
Last time they came in a week saying that the snail mail never got to you.
I never got the bmw webasto running as I pickup a c8 one and now have fitted that.

Thanks vpug

Yes,standard free post (no hurry)

I hope you know the BMW one doesn't run on the Rover 's ?

[pete 75]

Can anybody help,i have a late Mk 2 cdti tourer with no fbh fitted,i have been offered one from a 2003 mk 1 saloon which is still fitted to the car,firstly are they interchangeable i no i need the complete unit and fuel pump is there anything else i need from the donor car.
Thanks Pete

[dinky d]

Check in cubby hole between front seats,there may be a timer to control the heater................Tom.:shrug:

[pete 75]

There is no timer unfortunately

[FrenchMike]

Hi Pete, have a look here:

http://www.the75andztclub.co.uk/forum/showthread.php?t=100297&highlight=fbh

[pete 75]

Hi Mike,Thanks for that.I have not been able to test the fbh as the car is a non runner,i see there are pcb problems with many of them does that happen on all models or just the earlier ones.

Pete

[FrenchMike]

Hi Mike,Thanks for that.I have not been able to test the fbh as the car is a non runner,i see there are pcb problems with many of them does that happen on all models or just the earlier ones.

Pete

The early type is more robust, so don't worry too much :}

[HarryM1BYT]

Hi Mike,Thanks for that.I have not been able to test the fbh as the car is a non runner,i see there are pcb problems with many of them does that happen on all models or just the earlier ones.

Pete

The early one is less troublesome with regards to its PCB, but being older, may have endured more wear.

The later units almost certainly will have a failed PCB. When buying one from a scrap car, you need to factor in that the unit may need need repair. Pumps also suffer severe rusting from the outside, so something else to allow for.

So far as the car is concerned, the two (early and late) are interchangeable.

Parts to ensure you get are the FBH, the air intake filter, the exhaust pipe and the pump plus its rubber mounts (keeping in mind the above warning). The pump metal brackets rot away even faster than the pump, but they are easy to fabricate.

[pete 75]

Harry and Mike many thanks for your helpfull replies.

Pete

[Martin_J]

Something like "JE" if it can help :duh:

Mike, thanks a lot!

It is a double diode BAV99.

Martin

[Jules]

I have some of those diodes from TV repair days.......................where they might be in the sheds is another subject :eek:

[Drakes]

I have sneaked on here from a Land Rover forum as somebody suggested there is a wealth of knowledge on here.

I have 3 Webasto heaters all of which are unknown, 1 is from a BMW 7s, 1 from a Peugeot 807 and finally 1 from a 75. All appear similar and I have tried to use the diagnostic software on all 3 of them. The only on that responds is the BMW and I can read the spec and stored fault codes. The other 2 just hang on the "Initialisation" page. I have tried setting the device to W-Bus and also the Rover and Peugeot settings but no luck. The BMW one responds on the W-Bus so I know the software and OBDII are working fine.

The plan is to try and get a least one working and then fit it to the Land Rover.

Any help from somebody who can guide me with the software/diagnosis would be much appreciated.

Keith

[FrenchMike]

I have sneaked on here from a Land Rover forum as somebody suggested there is a wealth of knowledge on here.

I have 3 Webasto heaters all of which are unknown, 1 is from a BMW 7s, 1 from a Peugeot 807 and finally 1 from a 75. All appear similar and I have tried to use the diagnostic software on all 3 of them. The only on that responds is the BMW and I can read the spec and stored fault codes. The other 2 just hang on the "Initialisation" page. I have tried setting the device to W-Bus and also the Rover and Peugeot settings but no luck. The BMW one responds on the W-Bus so I know the software and OBDII are working fine.

The plan is to try and get a least one working and then fit it to the Land Rover.

Any help from somebody who can guide me with the software/diagnosis would be much appreciated.

Keith

As much as i know,the two Rover types run without kbus need.

About the others,i think the software are different and dependant on the car.

Mike

[HarryM1BYT]

As much as i know,the two Rover types run without kbus need.

Mike

What bit I have learned, is that the later Rover version has Kbus, but it is only used for diagnostics. There is software in there which could have allowed it to be operated via K-bus, likely from the Hi-Line ICE system, but it was never implemented. On the BMW I understand it was and its ICE system could command the FBH.

T4 can interrogate via the K-bus on the later type for faults and possibly control it too I would expect.

The later (assuming it is the later version) Rover FBH hanging, probably means the PCB is faulty which is quite common. Mike, for a small fee, can repair these PCB's.

I think I am correct in suggesting that the earlier Rover FBH has no k-bus system at all (Mike ?)

There is much more information on the later Rover FBH to be found, if you click on the link in my sig.

[FrenchMike]

What bit I have learned, is that the later Rover version has Kbus, but it is only used for diagnostics. There is software in there which could have allowed it to be operated via K-bus, likely from the Hi-Line ICE system, but it was never implemented. On the BMW I understand it was and its ICE system could command the FBH.

T4 can interrogate via the K-bus on the later type for faults and possibly control it too I would expect.

The later (assuming it is the later version) Rover FBH hanging, probably means the PCB is faulty which is quite common. Mike, for a small fee, can repair these PCB's.

I think I am correct in suggesting that the earlier Rover FBH has no k-bus system at all (Mike ?)

There is much more information on the later Rover FBH to be found, if you click on the link in my sig.

Totally agree Harry,

Consequently,the Rover's have a big advantage :they can be used
as stand alone heating system .:}

Mike

[FrenchMike]

I have sneaked on here from a Land Rover forum as somebody suggested there is a wealth of knowledge on here.

I have 3 Webasto heaters all of which are unknown, 1 is from a BMW 7s, 1 from a Peugeot 807 and finally 1 from a 75. All appear similar and I have tried to use the diagnostic software on all 3 of them. The only on that responds is the BMW and I can read the spec and stored fault codes. The other 2 just hang on the "Initialisation" page. I have tried setting the device to W-Bus and also the Rover and Peugeot settings but no luck. The BMW one responds on the W-Bus so I know the software and OBDII are working fine.

The plan is to try and get a least one working and then fit it to the Land Rover.

Any help from somebody who can guide me with the software/diagnosis would be much appreciated.

Keith

As said above,fit the Rover one and forget the software ...
If the PCB is faulty,(see my diagnostics),i can help...:}

Mike

[Drakes]

I have read your thread and found it very interesting. I was trying to get the Webasto thermo test software to run on the heaters before I got as far as servicing or installing them to see if any faults had been logged which might imply I am wasting my time with any of the units if they were beyond repair. Thought the software could guide me in the servicing that might be required.
The Peugeot unit is 2006 so I thought this should work on the W-Bus setting of the software the same as the BMW (2005). I thought all models since 2000 are meant to be W-Bus units. The Rover unit is impossible to read the label but the year does start 19.

Keith

[FrenchMike]

I have read your thread and found it very interesting. I was trying to get the Webasto thermo test software to run on the heaters before I got as far as servicing or installing them to see if any faults had been logged which might imply I am wasting my time with any of the units if they were beyond repair. Thought the software could guide me in the servicing that might be required.
The Peugeot unit is 2006 so I thought this should work on the W-Bus setting of the software the same as the BMW (2005). I thought all models since 2000 are meant to be W-Bus units. The Rover unit is impossible to read the label but the year does start 19.

Keith

To make a Rover unit running,you simply have to connect pin 1 to +batt :}

[HarryM1BYT]

IThought the software could guide me in the servicing that might be required.

Keith

Nothing too difficult in the servicing, read this...

http://www.the75andztclub.co.uk/forum/showpost.php?p=877768&postcount=5

[Drakes]

Harry and Mike

I see I am speaking to you both. I understand it is simple to get the unit running and all I intend to use is a simple on/off switch. The use of the diagnostic software is really more of a curiosity thing having got it to work on the BMW unit and been able to read any logged faults and historic data is quite interesting even if it is not needed to run or service the unit. Now I have played with the software a bit it is frustrating more than anything else that I can not get it to work on the other units.

Keith

[Jakg]

My FBH hasn't been firing up recently.

I have the older one.

I connected pin 3 to ground, and ran the test - it stopped after 5 minutes and 10 seconds.

It did appear to fire up about half way through (and made quite a lot of white smoke when it did), and the coolant started to warm.

The unit was serviced by me last year.

The temp was about 5° C, and I have a new uprated LR FBH thermostat fitted.

Thoughts on a postcard.

[FrenchMike]

My FBH hasn't been firing up recently.

I have the older one.

I connected pin 3 to ground, and ran the test - it stopped after 5 minutes and 10 seconds.

It did appear to fire up about half way through (and made quite a lot of white smoke when it did), and the coolant started to warm.

The unit was serviced by me last year.

The temp was about 5° C, and I have a new uprated LR FBH thermostat fitted.

Thoughts on a postcard.

Hi Jack

To me, 5 minutes means PCB out of the picture

White smoke and coolant warm are good signs

Possible flame out :shrug:

http://rovermg1.free.fr/rovermg/images/ClavDlk0BJGEuv5rlhgH.jpg

http://rovermg1.free.fr/rovermg/thumbnails/ClavDlk0BJGEuv5rlhgH.jpg (http://rovermg1.free.fr/rovermg/images/ClavDlk0BJGEuv5rlhgH.jpg)

(if you start it by grounding pin3 ,it't the second type (kbus interfaced on pin 2)

Keep the connection ON while all the cycle

a nearly 6 years adventure !!!

Mike

[mrdexter1]

Recently finished fitting a rover 75 fbh to my megane cc and got it all up and running off a remote switch for pre heating.... and then...


I discover webasto offer a kit to upgrade the system to direct all the heat to the heater matrix which offers very rapid interior warming and defrost, reduced fuel and electrical consumption... on contacting webasto uk they knew nothing about it.

I set about replicating the webasto kit and now have a fully working remote switchable -

heater matrix only - 9 minutes to defrost and warm car

heater priority.

standard engine and heater pre heat.

this is a video of before I fitted the remote switch.


https://www.youtube.com/results?search_query=webasto+defrost


get in you beauty , I love my hot early mornings....

[Jakg]

Hi Jack

To me, 5 minutes means PCB out of the picture

White smoke and coolant warm are good signs

Possible flame out :shrug:

http://rovermg1.free.fr/rovermg/thumbnails/ClavDlk0BJGEuv5rlhgH.jpg (http://rovermg1.free.fr/rovermg/images/ClavDlk0BJGEuv5rlhgH.jpg)

(if you start it by grounding pin3 ,it't the second type (kbus interfaced on pin 2)

Keep the connection ON while all the cycle

a nearly 6 years adventure !!!

MikeCould you expand on what you mean by flameout?

Should it run indefinately in the test mode, or will it stop after a while anyway?

[FrenchMike]

Yes,it MUST run indefinately in the test mode as long as you maintain the connection.
BUT when the internal temp reaches 73 degrees,it passes in half load .
And if the temp arrive at 77 degrees,then shut down and idle .

At full load,you can hear in the cabin the click click of the pulsing pump at
the rate of 2.38 per sec .

If ,for one reason or another the flame extinguishes,it enter the mode described above.

After 3 trials ,you have to do a reset (engine ignition OFF,remove /reinsert fuse F8)

Mike

[Jakg]

Yes,it MUST run indefinately in the test mode as long as you maintain the connection.
BUT when the internal temp reaches 73 degrees,it passes in half load .
And if the temp arrive at 77 degrees,then shut down and idle .

At full load,you can hear in the cabin the click click of the pulsing pump at
the rate of 2.38 per sec .

If ,for one reason or another the flame extinguishes,it enter the mode described above.

After 3 trials ,you have to do a reset (engine ignition OFF,remove /reinsert fuse F8)

Mike
When I started the engine after the test, coolant temp was 18° C, so it sounds like a flameout.

What is likely to cause it?

[FrenchMike]

It's important to know if 30 sec after starting you can hear the clik click of the
fuel pump at least for a while .
then check for fuel pulsing at the end of the little plastic pipe

Typical cold start :

The blue line is the fuel pulsing rate
green =fan
red = glow plug
http://rovermg1.free.fr/rovermg/images/pEQJ2EXKZpHBACXqzIz4.jpg


http://rovermg1.free.fr/rovermg/thumbnails/pEQJ2EXKZpHBACXqzIz4.jpg (http://rovermg1.free.fr/rovermg/images/pEQJ2EXKZpHBACXqzIz4.jpg)

[HarryM1BYT]

When I started the engine after the test, coolant temp was 18° C, so it sounds like a flameout.

What is likely to cause it?

That is easy to answer...

Most likely cause is that it needs a service, if you are sure it is getting air (filter not blocked) and adequate fuel (plenty of fuel in the tank and the pump working properly, no air leaks on the pipe).

The fuel pick up point is I understand, set some way above the tank bottom, so the FBH will be deprived of fuel, whilst there is still fuel in the tank.

Hard carbon build up around the glow pin and the metal mesh, can cause the glow pin not to work as it should and the fuel to be not properly atomised. I detailed how to service the FBH properly, several years ago.

[Jakg]

It's important to know if 30 sec after starting you can hear the clik click of the
fuel pump at least for a while .
then check for fuel pulsing at the end of the little plastic pipe

Typical cold start :

The blue line is the fuel pulsing rate
green =fan
red = glow plug

http://rovermg1.free.fr/rovermg/thumbnails/pEQJ2EXKZpHBACXqzIz4.jpg (http://rovermg1.free.fr/rovermg/images/pEQJ2EXKZpHBACXqzIz4.jpg)Surely if it's getting no fuel, it wouldn't of fired up at all? But yes, I can test that.That is easy to answer...

Most likely cause is that it needs a service, if you are sure it is getting air (filter not blocked) and adequate fuel (plenty of fuel in the tank and the pump working properly, no air leaks on the pipe).

The fuel pick up point is I understand, set some way above the tank bottom, so the FBH will be deprived of fuel, whilst there is still fuel in the tank.

Hard carbon build up around the glow pin and the metal mesh, can cause the glow pin not to work as it should and the fuel to be not properly atomised. I detailed how to service the FBH properly, several years ago.
I've not cleaned air intake specifically, but I did strip the unit down and give it a basic service last year.

I always have >1/4 tank of fuel. My pump was also brand new a few years back.

I've found a post from myself back in 2011 - http://www.the75andztclub.co.uk/forum/showthread.php?t=73341 - which seems to suggest that I've already sent the PCB to Mike, who said it's ok, but that also it looks like I've had this problem all along (coming on, but then going off).

My next thought is to try servicing it again, but this time pay special attention to the combustion chamber, testing the glow pin, and also think about replacing the gaskets as I know all of mine have had it (nb I know this is a matter of debate!).

I do remember removing quite a bit of carbon last time, though.

[sln8458]

Just a thought which maybe those who know more can verify.

I think the glow pin doubles up as the flame failure sensor, so you may have a borderline glow pin. I seem to remember Mike having a trick to fool the system into thinking the glow pin is ok (21w bulb??)

As I say just a thought:shrug:

SteveN

[FrenchMike]

Just a thought which maybe those who know more can verify.

I think the glow pin doubles up as the flame failure sensor, so you may have a borderline glow pin. I seem to remember Mike having a trick to fool the system into thinking the glow pin is ok (21w bulb??)

As I say just a thought:shrug:

SteveN

How are you Steve ?
you are right ,here is what to do :

The goal is to lower the glow plug resistor at starting .

53225
http://www.the75andztclub.co.uk/forum/attachment.php?attachmentid=53225&d=1444808540

Mike

[HarryM1BYT]

As said, the carbon is very hard and it can look as if you have it cleaned out and down to bare metal, but the cleaning the carbon out is the primary job when servicing. Any left in the mesh, or around the glow pin, will cause flame failures.

The glow pin acts initially as an ignition source for the fuel, then once lit, it acts as a combustion monitor. The PCB measures the varying resistance of the glow pin, to determine whether it is burning correctly or not. Carbon around the pin, will hamper its ability to both ignite the mixture and measure the combustion temperature.

As said in my How To, the best way to break up the carbon in the mesh, is using hard pressure with a blunt object, pressing on the mesh. Don't attempt to pick the carbon out of the mesh, or the mesh will be destroyed. You have to crumble it, to the point where it can fall out.

[sln8458]

How are you Steve ?
you are right ,here is what to do :

The goal is to lower the glow plug resistor at starting .

53225

Mike

Hi Mike,
I'm well :} though the same can not be said of my FBH :mad: I sent you an email this morning.

SteveN

[Jakg]

My FBH hasn't been firing up recently.

I have the older one.

I connected pin 3 to ground, and ran the test - it stopped after 5 minutes and 10 seconds.

It did appear to fire up about half way through (and made quite a lot of white smoke when it did), and the coolant started to warm.

The unit was serviced by me last year.

The temp was about 5° C, and I have a new uprated LR FBH thermostat fitted.

Thoughts on a postcard.Could you expand on what you mean by flameout?

Should it run indefinately in the test mode, or will it stop after a while anyway?

When I started the engine after the test, coolant temp was 18° C, so it sounds like a flameout.

What is likely to cause it?

Surely if it's getting no fuel, it wouldn't of fired up at all? But yes, I can test that.
I've not cleaned air intake specifically, but I did strip the unit down and give it a basic service last year.

I always have >1/4 tank of fuel. My pump was also brand new a few years back.

I've found a post from myself back in 2011 - http://www.the75andztclub.co.uk/forum/showthread.php?t=73341 - which seems to suggest that I've already sent the PCB to Mike, who said it's ok, but that also it looks like I've had this problem all along (coming on, but then going off).

My next thought is to try servicing it again, but this time pay special attention to the combustion chamber, testing the glow pin, and also think about replacing the gaskets as I know all of mine have had it (nb I know this is a matter of debate!).

I do remember removing quite a bit of carbon last time, though.

I took the unit off and serviced it again, this time doing a much more thorough job - replacing all the gaskets, properly cleaning the burned and combustion chamber etc.

Put it back together and it looks to be working properly now - or at least it fires up and runs for a lot longer than 5 minutes!

I also replaced the mounting bolts (20mm M6 flanged) as mine had had it.

[Jakg]

I took the unit off and serviced it again, this time doing a much more thorough job - replacing all the gaskets, properly cleaning the burned and combustion chamber etc.

Put it back together and it looks to be working properly now - or at least it fires up and runs for a lot longer than 5 minutes!

I also replaced the mounting bolts (20mm M6 flanged) as mine had had it.

Another day, another question!

Unit fires up doing the pin 3 test for >10 minutes, get hot, all looks good.

When the engine fires up, the unit comes on, but then after a couple of minutes turns off, often with a little white smoke?

[FrenchMike]

Another day, another question!

Unit fires up doing the pin 3 test for >10 minutes, get hot, all looks good.

When the engine fires up, the unit comes on, but then after a couple of minutes turns off, often with a little white smoke?

Hi Jack,

Two reasons that could stop it with engine ON (Under control of Pin 1)

-coolant temperature higher than 77 degrees

-external temp more than 5 degrees :shrug:

Mike

[Jakg]

Hi Jack,

Two reasons that could stop it with engine ON (Under control of Pin 1)

-coolant temperature higher than 77 degrees

-external temp more than 5 degrees :shrug:

Mike
This morning, it ran for 3 minutes with the engine on, then a big plume of white smoke, then 2 minutes with the fan on max and it cut out.

Coolant temp was 40° C at most, ambient was 7.5° C (I have the Land Rover temperature sensor that I think clicks on at 9° C?)

Again, works fine with the Pin 3 test.

Could it be PCB related? I did damage mine with a screwdriver through one edge!

[FrenchMike]

This morning, it ran for 3 minutes with the engine on, then a big plume of white smoke, then 2 minutes with the fan on max and it cut out.

Coolant temp was 40° C at most, ambient was 7.5° C (I have the Land Rover temperature sensor that I think clicks on at 9° C?)

Again, works fine with the Pin 3 test.

Could it be PCB related? I did damage mine with a screwdriver through one edge!

I would say ,if it works fine with control on pin 3,the PCB is OK

Check the voltage on pin 1 (must stay on +12 while the run) .

If any doubt about the one damaged,send it to me for test :}

Mike

[Jakg]

I would say ,if it works fine with control on pin 3,the PCB is OK

Check the voltage on pin 1 (must stay on +12 while the run) .

If any doubt about the one damaged,send it to me for test :}

Mike

Ok, had another look.

11° C ambient, it fired up for maybe 20 seconds then cut out (???).

I'm not quite sure of the pin numberings (is there a pinout for the older FBH?) but if I applied +12v to Pin 3 to fire it up, then Pin 1 must be the one in line with it but at the very front - in which case this was around 0.15-0.5v with it running after being started by the car, or by my remote control.

[FrenchMike]

Ok, had another look.

11° C ambient, it fired up for maybe 20 seconds then cut out (???).

I'm not quite sure of the pin numberings (is there a pinout for the older FBH?) but if I applied +12v to Pin 3 to fire it up, then Pin 1 must be the one in line with it but at the very front - in which case this was around 0.15-0.5v with it running after being started by the car, or by my remote control.

Well,so you have the first one (66232)

Pin3 is the one showed on the pict. (parking heater)

http://rovermg1.free.fr/rovermg/images/vaFHCXKVXo37GpGeGkFV.jpg

http://rovermg1.free.fr/rovermg/thumbnails/vaFHCXKVXo37GpGeGkFV.jpg (http://rovermg1.free.fr/rovermg/images/vaFHCXKVXo37GpGeGkFV.jpg)

Pin 1 on all model is the "normal " fonction driven by the ECU.
maintained at +12 v all the run long.

:smiley:

Mike

[Jakg]

Ok in which case, I am applying 12v to pin 1 to fire up the heater, and I am getting ~0.15-0.5v on Pin 3. Does this mean I've wired it up wrong?

[FrenchMike]

Ok in which case, I am applying 12v to pin 1 to fire up the heater, and I am getting ~0.15-0.5v on Pin 3. Does this mean I've wired it up wrong?

Sorry Jack,you're not allowed to apply any external 12 volt on pin 1.

It's alreary occupied ..and you risk damaging the ECU !!!

pin 1 or 3 are entries so no voltages on them at rest .

If you want to force it,apply 12 volts on pin 3.

Mike

[Jakg]

Sorry Jack,you're not allowed to apply any external 12 volt on pin 1.

It's alreary occupied ..and you risk damaging the ECU !!!

pin 1 or 3 are entries so no voltages on them at rest .

If you want to force it,apply 12 volts on pin 3.

Mike

ECU of the car, or ECU of the FBH?

This would explain why when I put the FBH on, the low oil level light comes on the IPK with the ignition off!

It's been that way for years and somehow works, but it looks like I've got a job for this weekend...

[FrenchMike]

ECU of the car, or ECU of the FBH?

This would explain why when I put the FBH on, the low oil level light comes on the IPK with the ignition off!

It's been that way for years and somehow works, but it looks like I've got a job for this weekend...

ECU of the CAR !!!!!

http://rovermg1.free.fr/rovermg/images/hJp6znBnEAp5OxnmSiwA.jpg

http://rovermg1.free.fr/rovermg/thumbnails/hJp6znBnEAp5OxnmSiwA.jpg (http://rovermg1.free.fr/rovermg/images/hJp6znBnEAp5OxnmSiwA.jpg)

Finger crossed ....

[decebalus]

Does anybody knows if the early model 66232C is a direct swap with the new PCB model 98570B or it's a complicated replacement? Thanks

[FrenchMike]

Does anybody knows if the early model 66232C is a direct swap with the new PCB model 98570B or it's a complicated replacement? Thanks

Yes , and no kbus (pin 2 not connected)

Mike

[Jakg]

Another day, another problem!

When setup as a parking heater, my FBH only ever gets the coolant up to about 55° C at most, even after >20 minutes.

Yesterday I used it and noticed a black patch under the car.

Today I came back (I put it on as I walk my dog) to find a lot of smoke, a smell of diesel and a big sooty patch under the car. The coolant was at 25° C so it'd done something, but I'm not quite sure what!

All I can think of is too little air would cause incomplete combustion = soot?

I serviced the unit only a few months back.

[FrenchMike]

Another day, another problem!

When setup as a parking heater, my FBH only ever gets the coolant up to about 55° C at most, even after >20 minutes.

Yesterday I used it and noticed a black patch under the car.

Today I came back (I put it on as I walk my dog) to find a lot of smoke, a smell of diesel and a big sooty patch under the car. The coolant was at 25° C so it'd done something, but I'm not quite sure what!

All I can think of is too little air would cause incomplete combustion = soot?

I serviced the unit only a few months back.

Hi Jack,

Remove the foam Inside the air inlet and see...

Mike

[kael]

I've been reading through this whole thread. Two things keep me wondering;
1. Measuring the suspected SMD resistors: can this been done while they are soldered to the PCB? Perhaps the reading is not correct then as the Ohm-meter finds another (lower resistance) way in the PCB circuit to measure.
2. About disconnecting or resetting the FBH: Do both models (earlier and later) FBH need do disconnecting the plugs (2pin & 6pin) in proper order.
In other words, what is exactly the correct procedure?

[FrenchMike]

I've been reading through this whole thread. Two things keep me wondering;
1. Measuring the suspected SMD resistors: can this been done while they are soldered to the PCB? Perhaps the reading is not correct then as the Ohm-meter finds another (lower resistance) way in the PCB circuit to measure.
2. About disconnecting or resetting the FBH: Do both models (earlier and later) FBH need do disconnecting the plugs (2pin & 6pin) in proper order.
In other words, what is exactly the correct procedure?

Nothing particular,respect the rules ,never feed any IC via inputs with power
supply OFF

[another_clean_sheet]

Nothing particular,respect the rules ,never feed any IC via inputs with power
supply OFF

What this means is you disconnect the 6 pin plug first and then the 2 pin supply plug. Reconnect 2 pin then the 6 pin plug.

[FrenchMike]

What this means is you disconnect the 6 pin plug first and then the 2 pin supply plug. Reconnect 2 pin then the 6 pin plug.

Perfectly true :}

[kael]

OK that is clear about the connecter sequence.
But what about my other question, about measuring the suspected SMD resistors with the multimeter while the resistors are still soldered? Will that give a proper read out? I suppose you better of by first desoldering it (at least 1 side).

[kael]

In Post nr 192 FrenchMike says:
Sorry Jack, you're not allowed to apply any external 12 volt on pin 1.
Apply 12V on pin 3
In the FAQ:
http://www.the75andztclub.co.uk/forum/showthread.php?t=100297&highlight=fbh (http://www.the75andztclub.co.uk/forum/showthread.php?t=100297&highlight=fbh)
under the section Ready to test I see:
Note - Model 66232C (early) requires +12 volt to pin 1
Whereas Model 98570B (later) requires earth to pin 3
Are we talking about the same thing here?

[Union Wheels]

Hi Kael,
just to make it clear, all models are normally switched on by applying 12 volts to pin 1.

To force start-up on model 98570B connect pin 3 to chassis.

To force start-up on model 66232C connect pin 3 to 12 volt supply.

If you wish to start-up either unit with pin 1, put a diode in series with this new supply.

Hope this clears things up, Pete.

[FrenchMike]

OK that is clear about the connecter sequence.
But what about my other question, about measuring the suspected SMD resistors with the multimeter while the resistors are still soldered? Will that give a proper read out? I suppose you better of by first desoldering it (at least 1 side).

I can't imagine desoldering them before test ...:duh:

[FrenchMike]

In Post nr 192 FrenchMike says:

In the FAQ:
http://www.the75andztclub.co.uk/forum/showthread.php?t=100297&highlight=fbh (http://www.the75andztclub.co.uk/forum/showthread.php?t=100297&highlight=fbh)
under the section Ready to test I see:

Are we talking about the same thing here?

Sorry,all is said:

you're not allowed to apply any external 12 volt on pin 1.

It's alreary occupied ..and you risk damaging the ECU !!!

If you want to force it,apply 12 volts on pin 3. (66232)

Mike

[HarryM1BYT]

You can avoid the risk of damaging the FBH ECU, by connecting/ disconnecting the two plugs in the wrong order, by cutting the data wire.

It serves no useful function on the 75, other than when connected up to a T4 for diagnostics. On the BMW the data wire allows the FBH to be started by the radio unit, but not the 75.

[kael]

Last year I added a heated seat switch to manually switch on the FBH and 3 months ago I also added GSM control. I also have a LED connected to pin6 so I can see the pulses for the FBH fuel pomp.
That all worked fine until last week when I noticed the FBH didn't fired up anymore.
With manual override my 98570B, I timed the starting sequence;
the fan runs for 2'2" then stops and after 5" it starts again for another 2' then it stops again and nothing more.
I don't hear the pump clicking neither do I see the pulses in the attached 12V led on pin 6.
I checked the PCB and changed the 3 resistors. The 47K showed infinite, the two 4K7's I could measure first but not after changing the 47K... I thought. To make sure I changed all 3.
But still no change.
The glow plug measures about 0.5 Ohm as far as my meter show this correct.
Any ideas for the next steps to try? I'm really missing my FBH on short rides in these cold days now.

[FrenchMike]

The pulsing pump runs when and only when all the Securities are clear :shrug:

Here is a faulty glowplug timing:

http://rovermg1.free.fr/rovermg/thumbnails/iFrrQz81GXHA2f8ZMvX1.jpg (http://rovermg1.free.fr/rovermg/images/iFrrQz81GXHA2f8ZMvX1.jpg)

Not easy to measure the glow plug resistor without a millihom meter ...

in case

http://sales.butlertechnik.com/webasto-thermo-top-e-c-p-z-glowpin-kit-9017813b

Mike

[HarryM1BYT]

The glow plug measures about 0.5 Ohm as far as my meter show this correct.
Any ideas for the next steps to try? I'm really missing my FBH on short rides in these cold days now.

You cannot measure the extremely low resistance with an ordinary meter, the only way without buying special equipment is to measure the current flow at a known voltage and use Ohms Law to calculate it.

Your symptoms suggest your PCB may need the expertise of FrenchMike.

[Union Wheels]

Hi kael,
have a look at the PC board where the glow pin plugs in, and see if there is any sign of a dry joint or high resistance connection on the plug pins. With high current low voltage operation a good joint is essential.

You may also like to check the operation of the electric water pump by feeling for the pulses in the water pipe.

Pete.

[Jakg]

Another day, another problem!

When setup as a parking heater, my FBH only ever gets the coolant up to about 55° C at most, even after >20 minutes.

Yesterday I used it and noticed a black patch under the car.

Today I came back (I put it on as I walk my dog) to find a lot of smoke, a smell of diesel and a big sooty patch under the car. The coolant was at 25° C so it'd done something, but I'm not quite sure what!

All I can think of is too little air would cause incomplete combustion = soot?

I serviced the unit only a few months back.

Hi Jack,

Remove the foam Inside the air inlet and see...

Mike

I removed the foam inlet and it solved my problem, briefly. Then it came back!

I know - I've posted too much in this thread!

Mike - can I post you the PCB? Are you happy to take a look?

[FrenchMike]

I removed the foam inlet and it solved my problem, briefly. Then it came back!

I know - I've posted too much in this thread!

Mike - can I post you the PCB? Are you happy to take a look?

Hi Jack,

Yes, but i doubt ...(i never encounter this)

Two ways :

too much fuel delivered

Or more plausible your fan is feeble ?

normally it sounds rather like an hovercraft ...:shrug:

[Jakg]

Hi Jack,

Yes, but i doubt ...(i never encounter this)

Two ways :

too much fuel delivered

Or more plausible your fan is feeble ?

normally it sounds rather like an hovercraft ...:shrug:
It gets weirder - when I run the unit using the pin whatever test, it runs fine and warms up to 50-something° C, no smoke.

When I start the engine and let it warm up - then it warms up a bit then smoke starts pouring out.

The fact it does differing things in different "modes" of operation was what lead me to think it was the PCB.

[HarryM1BYT]

It gets weirder - when I run the unit using the pin whatever test, it runs fine and warms up to 50-something° C, no smoke.

When I start the engine and let it warm up - then it warms up a bit then smoke starts pouring out.

The fact it does differing things in different "modes" of operation was what lead me to think it was the PCB.

Just to throw an idea into the pot...

It reads as if it might be completely random. I know you say you have given it a clean out and service, but it is easy to mistake hard burnt on carbon for part of the combustion chamber structure. Make no mistake - burnt on carbon is very hard and will need to be chipped away.

Like FrenchMike, I doubt the PCB is at fault - you need to look elsewhere. As Mike says, it should sound like a small jet engine. The speed of which and noise should gradually ramp itself up, after the combustion becomes established, to full speed. It should then ramp down as it nears shut off temperature.



Any carbon around the glow pin or the mesh at the back could cause the miss-fires you are complaining about.

[Union Wheels]

Hi Jakg,
is it possible that the start up voltage to pin 1 of the 6 pin plug is intermittent or low.

I have read somewhere that the wiring between the alternator, temperature sensor and pin 1 of the heater can become corroded near to the temperature sensor plug.

Just an idea, Pete.

[Jules]

FBH Golden rules recap :smilie_re:

Most common later type 98570B
+12v to pin1 or ground pin 3 to test.

Early Type 66232C needs 12v to pin 1 or 3 instead
(both blue capacitors touching type)

If disconnecting PCB:

UNPLUG 6 PIN FIRST THEN 2 PIN POWER PLUG

If reconnecting
REFIT POWER PLUG FIRST
6 PIN LAST

[Jakg]

Hi Jakg,
is it possible that the start up voltage to pin 1 of the 6 pin plug is intermittent or low.

I have read somewhere that the wiring between the alternator, temperature sensor and pin 1 of the heater can become corroded near to the temperature sensor plug.

Just an idea, Pete.
That certainly sounds possible - I've had wiring corrosion in that area before.

Do you have any more info on this please? Are you sure it's pin 6 on the earlier FBH? What voltage should I be expecting?

[Jules]

Pete didn't say Pin 6 he said 6 pin plug !!!
I refer you to read my #218 again ;)

[Union Wheels]

Hi Jakg,

My post says pin 1 of the 6 pin plug.

This applies to both the early and later versions.

You are looking for 12volts.

Pete.

[Jakg]

Pete didn't say Pin 6 he said 6 pin plug !!!
I refer you to read my #218 again ;)

Hi Jakg,

My post says pin 1 of the 6 pin plug.

This applies to both the early and later versions.

You are looking for 12volts.

Pete.

Sorry, long day - will check and update.

[Alpejohn]

Hi guys,

I am so amazed of all the webasto knowlage here!

I dont own a Rover, but seen a few questions from bmw owners while reading through this thread. :D And as no one is close to this knowlage on my local bmw forum i just had to register to ask a few questions. :wink2:


1.
In my Bmw E39 with factory fitted TT Z/C (working as a parkheater), the combustion fan has startet to behave in a "different" way so to speak. Earlyer when it all worked fine, i turned on the heater, the combustion fan would start at low speed and run for some seconds, then stop. And the fuel pump would start clicking. But now, it start at slow speed, then the speed increases, not sure of full speed, but it might be. And it continues to run while the webasto is powering up. It works fine in every other way, it warms up and runs for 30 minutes and turn off. Its just this odd thing with the fan that suddenly started.

I have had the heater out and taken it apart, cleaned the chamber, heater pin, heat exchanger and all that, mounted back with new gaskets. Also changed the combustion air fan as the old one had worn out bearings so it made a lot of noice. But the fan problem was there before i did that too.

What can cause this? :}


2.
Found a cheap webasto online for 56£, so i just had to buy it. It looked almost brand new on the outside so thought i could fix it and have it as a spare. This was apparantly of a bmw E46.
Owner said it fired up when he moved the car that it came from.

So i got it on my bench, and put 12v to it, and the combustion fan started immediantly to run on full speed. And continued for a while, and then some erratic speed befor it stopped. Broken ECU was the first thing that came to my mind. So i connected my webasto diagnostic software to it to see whats up (The thermotest or whats it called). Got connected, and there was 3 faults. Dont have the screenshot right here, so i dont remember exactly, but it was a problem with the waterpump (wich i couldnt get going with 12 volts so its probably dead), and something with the combustion fan interuption or disturbence or something like that. (Can check the screenshot later).

After i took it apart, it was clear that it had some kind of issue, as whe back of the burner insert was covered in sot, everything was black, combustionfan and everything. The exhaust was also almost clogged with sot. And after taking out the burner insert there where sot everyehere.


I meassured the glow pin, it gave me 0.4 ohms, so it should be fine.
Combustion fan it selfe is working.
Waterpump, nothing happends when applying 12 volts even changed the polarity and nothing.

So i removed the ECU, it looks in perfect condition, no sign of moisture or any other problem. Seems brand new. When i connect 12 volts to it, i get a constant 2.5 volts at the combustion air fan and water pump. I think also i got 2.5 at the glow plug but om not sure. After a while it could drop to 0 volts at both fan and pump, but before i knew it it was back.

I had the computer connected when i meassured, it seemed as the voltage came back when i connected the software. And when i tried to run the fan from the TT software, it wouldnt start. I managed to start the glow pin from the software, and i meassurend around 11 volt.
The whole ECU seems a bit unstable.

I removed the white sticky glue from the ECU, couldnt see any special problem. Tried to meassure the resistors, but do i have to remove them from the board to properly meassure them, or should i be able to do that while they sit on the board?

I managed to meassure on resistor at the rated ohm. I guess the ECU has some problems though.

What do you think guys? :)


And sorry for not having a Rover, but this is the best webasto thread i ever have come across! And i have learned a lot. So thank you so much for that! :}

Im from Norway, so my english isnt perfect! :P

[Arctic]

PROCEDURE BEFORE SENDING YOUR PCB.

At first, manage to permanently connect a wire between pin 3 of the 6 pin plug
And earth in order to forget the +5 degrees limit.

You must hear the turbine increasing its speed and the circulating pump running

If the noise stops after 2minutes and 7 seconds, then,

The pump fuel is faulty or PCB (more likely)

If it stops after 4 minutes then the glow plug resistor is too high.
(More than 0.4 ohm)
And ignition aborts.

However, it is useful to test each component before deciding that PCB is faulty.


http://rovermg1.free.fr/rovermg/thumbnails/sf0bxOiSpkFGEqtdqYxm.jpg (http://rovermg1.free.fr/rovermg/images/sf0bxOiSpkFGEqtdqYxm.jpg)

Since the work is easier to do than it was first time (no more IC to replace),

My PRICE is 43 £ (one hour work) postage included

Input check ,repair, and outpout control with report.

Mike


HI Mike.
Long belated thank you for sorting out the two PCB for our FBH we have, hopefully we will have time to get them fitted before the cold weather sets in over here cheers Arctic :bowdown:

[FrenchMike]

HI Mike.
Long belated thank you for sorting out the two PCB for our FBH we have, hopefully we will have time to get them fitted before the cold weather sets in over here cheers Arctic :bowdown:

Well Steve,i think the first frost will recall you it's time to fit :D

Cheers

Mike

[Walter]

Hi, Gsm fitted by fellow member yesterday, many thanks Attchus, Fbh shuts down at 4.05 mins, so glow plug resistor fault ? Is that on the circuit board, is it easy fix ?:duh:

[FrenchMike]

Hi, Gsm fitted by fellow member yesterday, many thanks Attchus, Fbh shuts down at 4.05 mins, so glow plug resistor fault ? Is that on the circuit board, is it easy fix ?:duh:

I guess you get any heat ? Try this :

http://rovermg1.free.fr/rovermg/thumbnails/RYnYrnq549Jt8pUA7K2t.jpg (http://rovermg1.free.fr/rovermg/images/RYnYrnq549Jt8pUA7K2t.jpg)

If with that you get smoke /heat ....Then ,you'll have to replace the glowplug :shrug:

Unless,you can send me your PCB for check/repair

Mike

[Walter]

I guess you get any heat ? Try this :

http://rovermg1.free.fr/rovermg/thumbnails/RYnYrnq549Jt8pUA7K2t.jpg (http://rovermg1.free.fr/rovermg/images/RYnYrnq549Jt8pUA7K2t.jpg)

If with that you get smoke /heat ....Then ,you'll have to replace the glowplug :shrug:

Unless,you can send me your PCB for check/repair

Mike Thanks Mike, have taken PCB from spare FBH, will try that next week , have you a link for stripping glowplug ?:duh:

[FrenchMike]

Thanks Mike, have taken PCB from spare FBH, will try that next week , have you a link for stripping glowplug ?:duh:

Yes Walter ,here is the Harry's How to service :

http://www.the75andztclub.co.uk/forum/showthread.php?t=100297

And the parts can be found here:

https://www.butlertechnik.com/webasto-heater-parts-c111/webasto-webasto-thermo-top-e-c-p-z-glowpin-kit-9017813b-p1646

Good luck
Mike

[Arctic]

HI Mike.
Long belated thank you for sorting out the two PCB for our FBH we have, hopefully we will have time to get them fitted before the cold weather sets in over here cheers Arctic :bowdown:

Well Steve,i think the first frost will recall you it's time to fit :D

Cheers

Mike

Hi Mike.
I thought I would let you know we fitted one of the FBH to my sons car and all is running as it should, we now only have to retro fit the T80 which all the wiring and the timer as been installed just got to get the main feed to it.

In the mean time i have another couple of FBH which i think may need sorting out i took out the PCB board on one yesterday and removed the white gloop, i have took a few photo's which are here below could you say from looking at them that they need the repair?

I will later today after cleaning out 5 manifold (diesel) remove the other PCB from the other FBH and add that here to if that is ok with you.

1st piece of gloop removed Fig 1
http://i67.tinypic.com/2le6s7d.jpg1

Close up of above Fig 2
http://i67.tinypic.com/dz9e9s.jpg2

2nd piece of gloop Fig 3
http://i64.tinypic.com/169papi.jpg3

Gloop removed from 2nd Fig 4
http://i64.tinypic.com/2nbyr6r.jpg4

Finally close up of area where both pieces of gloop resided Fig 5
http://i63.tinypic.com/2mfjub.jpg5

What did notice before the FBH which this PCB board belonged to before removing was that when plugged in and ignition turned on the FBH making a continuous noise as though it was cycling ? cheers Arctic

[FrenchMike]

Hi Steve ,from what you discribe ,the Fan circuitry is implied .

Check the 4.7k and 2k résistors around the capacitors firstly :shrug:

Mike

[Marky4x4]

http://s1338.photobucket.com/user/Mark_Woods/media/image_zpsaslie3a0.jpeg.html?sort=3&o=0

Hi Mike,
I have a 2004 Landrover Freelander with a faulty FBH.
I've been directed here from a Landrover forum thread about FBH faults.
Mine seems to be doing the same as yours, the fan will run for 2minutes, then stop, wait a few seconds and it'll try to start again.
I've powered pin 3, and as said the fan runs at full speed straight away. The fuel pump cannot be heard, there is no voltage supply to it out of the pcb, if it is shorted to supply it will click, also the resistance is ok @5.6ohms.
The water pump can be heard running and the heater body gets warm suggesting the glow plug is working.
A good 12v supply feeds the heater and the earth is good too.
My pcb is slightly different from the one in your photo.
If you agree the pcb could be the issue could you check it for me please?
Regards
Mark. :}

[FrenchMike]

http://s1338.photobucket.com/user/Mark_Woods/media/image_zpsaslie3a0.jpeg.html?sort=3&o=0

Hi Mike,
I have a 2004 Landrover Freelander with a faulty FBH.
I've been directed here from a Landrover forum thread about FBH faults.
Mine seems to be doing the same as yours, the fan will run for 2minutes, then stop, wait a few seconds and it'll try to start again.
I've powered pin 3, and as said the fan runs at full speed straight away. The fuel pump cannot be heard, there is no voltage supply to it out of the pcb, if it is shorted to supply it will click, also the resistance is ok @5.6ohms.
The water pump can be heard running and the heater body gets warm suggesting the glow plug is working.
A good 12v supply feeds the heater and the earth is good too.
My pcb is slightly different from the one in your photo.
If you agree the pcb could be the issue could you check it for me please?
Regards
Mark. :}

Hi Mark,no prob PM sent :}

[Arctic]

Hi Steve ,from what you discribe ,the Fan circuitry is implied .

Check the 4.7k and 2k résistors around the capacitors firstly :shrug:

Mike

Hi Mike.
I have removed the other PCB today and the white gloop the 4.7k & 2k resistors look ok but to an untrained eye :shrug: I have sent you a PM with regards to the above, cheers Arctic.

http://i66.tinypic.com/v8lbu0.jpg1

http://i67.tinypic.com/alnrj5.jpg2

http://i67.tinypic.com/2v8n3lz.jpg3

[Arctic]

HI Mike.
Cheers I have posted them off to you, always better to let the person whom knows to check & repair them ;) Arctic

[Marky4x4]

Hi Mike,

PCB on its way!

Cheers

Mark. :}

[bmw530d]

Hello Everyone, and happy new year !
I'm from France, so sorry for my english language approximations....
I've been searching for a long long time for the "how to repear the Webasto PCB".
That's the forum ! That's the guys who know !

So, before i tell you my Webasto story, i would like to really thanks all the members of this thread fro their contributions ! They really help me in my quest of Webasto working !

So the story...
My Webasto is fitted on a BMW E39 530d, 2001MY. It was not working when i bought the car. So i've purchased, on the web, a used Webasto from a BMW car. This have worked for one year, and.... failed.
My diagnose software (inpa) said "water pump short circuit" and "water pump open circuit". Very strange, isn't it ? Sometimes, after erasing errors in the aux heater and in the IHKA, the unit begins his starting cycle, begins to warm and failed after several minutes.INPA says "water pump short circuit" "water pump open circuit". But my water pump was OK. Under 12Vcc, it was running OK, no bad bearing noise. So, it was sure it was not the pump. I started to search around the Webasto PCBs (one has never worked, and the other worked for one year).I began to search around faulty SMD resistors, transistors, like FrenchMike told us.

On the older PCB, several resistors were out ! All the resistors were under the famous F....G white paste ! I agree with you when you told this paste contains agressive agent that destroys SMD components. So this cards need some new resistors (49,9kOhm, 4,75kOhm and 10kOhm 805 size in command). Waiting for this. Note that SMD 1206 size resistors were OK...

On the latest PCB, all resistors OK, so i began to search with my multimeter in ohmmeter mode and i've found the wolf ! The positive pin from water pump connector wasn't presenting a 25kOhm resistance from the groung, like positive pin from air fan connector did... What i've found is a bad continuity on an interside hole under the electrolytic capacitor 390µF. This track is for controlling the driving current of the water pump. The hole was like corroded, this always under the white paste. So this paste didn't only corroded the SMD resistors, but also copper tracks, coppered holes of the PCB. Repairing was easy, by passing à thin wire through the hole, and soldered on both sides on cleaned tracks.
Reconnect the PCB on the Webasto in the car and it works now very well.

[bmw530d]

Hello everybody !
To complete my last post, these are some pics of the diag and the repearing of my FBH...
In these pics we can see corroded holes located just under the 390µF capacitor (desoldered for the repear)
http://www.the75andztclub.co.uk/forum/imagehosting/388405884878cf0e52.jpg

And on the other side :
http://www.the75andztclub.co.uk/forum/imagehosting/38840588487c44dab0.jpg

Repearing by passing a thin wire from one side to the other, and soldering on clean parts of the corresponding copper track. As you can see, the solder is not very good on corroded past...
http://www.the75andztclub.co.uk/forum/imagehosting/38840588487dde56ca.jpg

Other side :
http://www.the75andztclub.co.uk/forum/imagehosting/3884058848817cb0d9.jpg

[Stephen Davies]

finally got one working on the bench, 47K resistor had gone bad, replaced with one of Maplin's last resistors, and its all working, very impressed with its heat output, even stuck an old central heating radiator on it, this could do a fine job of heating the workshop, now to attack the one in the car, now that i know what i'm doing
:}:}:drool4:

[HarryM1BYT]

finally got one working on the bench, 47K resistor had gone bad, replaced with one of Maplin's last resistors, and its all working, very impressed with its heat output, even stuck an old central heating radiator on it, this could do a fine job of heating the workshop, now to attack the one in the car, now that i know what i'm doing
:}:}:drool4:l

Frenchmike very kindly explained how to repair these FBH PCB's, so you can fix your own and I am sure you are not thinking of doing it - but it would be very unfair to begin repairing other's FBH PCB's.

[sln8458]

finally got one working on the bench, 47K resistor had gone bad, replaced with one of Maplin's last resistors, and its all working, very impressed with its heat output, even stuck an old central heating radiator on it, this could do a fine job of heating the workshop, now to attack the one in the car, now that i know what i'm doing
:}:}:drool4:


These heaters are used on narrow boats for heating and hot water!
I considered using one to heat the garden room (shed :D )

Steven

[Stephen Davies]

When I attacked the FBH in my car found the same failures 47K resistor sort of dissolved, as mike says possibly attacked by the wrigleys chewing gum stuck all over it, I have another spare...same again but unfortunately glow pins U/S in my two spares, so the known good one went in the car, now looking for new glow pins now..not thought about fixing others but if I get the spares going at least one will be going on ebay.

[Stephen Davies]

Hats off to French Mike but I would have figured it out myself, it’s my job to fix electronics...so if I choose to sell that skill I will, after all that’s how I make a living,
I rebuild vintage hi fi reel to reel tape machines for fun, but I could never hope to make any profit doing it, cost way too much to do, all that test gear and time don’t come free. Don’t worry I’m not about to start a cottage industry.

[Arminas]

Hello I need your help. I have bmw e39 webasto. And it shows me candle mistake. The candle itself is good, all smd are checked and they are good. I do not know where else to look for problems. I hope you can help me

[trebor]

Hello I need your help. I have bmw e39 webasto. And it shows me candle mistake. The candle itself is good, all smd are checked and they are good. I do not know where else to look for problems. I hope you can help me

Hi Arminas, when you say candle mistake do you mean glow plug and where are you reading the error, is it from the Webasto thermis test ?

[Arminas]

Hi Arminas, when you say candle mistake do you mean glow plug and where are you reading the error, is it from the Webasto thermis test ?

I think I found the problem with the glow plug. My error was that SMD resistor needs to be measured both sides. Now I'm waiting for details next week then I'll say how it went. But there's another problem, I have another pcb whose mistake is a circulation pump + everything shows 106 degrees though it is on my desk. Thermistor is 4.6Kom. Where do you need me to look?

I'm using a program WTT.

[Arminas]

http://i66.tinypic.com/303gso6.jpg

[Arminas]

I managed to fix the temperature mistake. I took out the thermistor and put it in again and it started showing good temperature. Theres just another problem with the water pump, the pump itself is good but WTT shows 2 problems, Circulating pump short circuit and Circulating pump interruption. I will be waiting for tips on where I could look for a problem.
http://i65.tinypic.com/2utohsi.png

[Devilish]

all smd are checked and they are good.
Can you post a picture after you checked the resistors.


it shows me candle mistake. The candle itself is good,.
What did you test to come to this conclusion.


Now I'm waiting for details next week then I'll say how it went.
What details, and how what went



You need to clear all errors


.

[Arminas]

Can you post a picture after you checked the resistors.



What did you test to come to this conclusion.



What details, and how what went



You need to clear all errors


.

1. I have 3 PCB and I checked everything it showed. 2. Cold resistance is 0.4kOm 3. Resistor 2002 20kOm. but theres no exact information yet, just my guess

http://i65.tinypic.com/smemvb.jpg

[Arctic]

Take a look under that chewing gum on the PCB it corrodes resistors under it.;)

https://i.imgur.com/doY1iJml.jpg1

https://i.imgur.com/K9x2XHjl.jpg2

[Arminas]

Take a look under that chewing gum on the PCB it corrodes resistors under it.;)


Thanks for the tip :) But the chewing gum was took off, and the picture is a example for information.:innocent::driving: