Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 17th December 2011, 22:00   #21
BigRuss
Premium Trader
 
BigRuss's Avatar
 
75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4)

Join Date: Jul 2007
Location: Liversedge, West Yorkshire
Posts: 5,405
Thanks: 1,105
Thanked 1,340 Times in 661 Posts
Default

The FBH if the outside temp. is low enough doesn't shut down even when the coolant is fully warm it goes into idle mode

72C = part load operation, anything above 76.5 the control idle mode cuts in, if the temperature drops then drops below 71C it will resume part load operation if the coolant temperature drops further as a result of heavy demand from the vehicle heater the FBH will resume full operation at 56C.

Shutdown proceedure after engine switched off:

175 seconds full load operation, 100 seconds part load.

Hope this helps.

Russ
__________________


Replacement Key Service
http://https://the75andztclub.co.uk/...d.php?t=244732
Full T4 Testbook diagnostics available.
Diesel ECU repair and replacement.
Options enabled or disabled as required.
Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160
MG 160 V6 to 177 upgrades available
P.M. for details.

Last edited by BigRuss; 17th December 2011 at 22:05..
BigRuss is offline   Reply With Quote
Old 17th December 2011, 22:02   #22
suffolk boy
This is my second home
 
fiat panda

Join Date: Sep 2009
Location: haverhill
Posts: 6,720
Thanks: 96
Thanked 586 Times in 526 Posts
Default

Quote:
Originally Posted by BigRuss View Post
When the heater has been running it will still operate after the ignition is turned off this is normal as it goes through a shutdown proceedure where ignition is cut, the internal fan then continues to cool down the burner, when cool enough the FBH will shutdown completely.

Please don't go cutting the K-bus wire with no good reason, if weird stuff is happening to other electric systems then unplug the FBH, your PCB is faulty.

There for a very good reason for the K-bus, it's there for diagnostic purposes, the cars ZCS coding includes the heater, when on T4 and running a diagnostic it will look for the heater via the K-bus if this is cut then it doesn't find it and you won't be able to run a full vehicle diagnostic.
Makes the time diagnosing faults an awful lot longer because then each ECU then needs to be accessed seperately. (the same goes for anything connected to the K-bus, CAN-bus or Nav-bus.)

Russ
looks like i have a little job to do on monday then
__________________
fiat panda 1.2 eco
suffolk boy is offline   Reply With Quote
Old 17th December 2011, 22:38   #23
HarryM1BYT
This is my second home
 
HarryM1BYT's Avatar
 
75 Contemporary SE Mk II 2004 Man. Sal. CDTi 135ps, FBH on red diesel, WinCE6 DD

Join Date: May 2010
Location: Leeds
Posts: 17,273
Thanks: 2,160
Thanked 2,061 Times in 1,586 Posts
Default

Quote:
Originally Posted by Jakg View Post
D'oh, bit late now... can always reconnect it if needs be. Don't see any T4 sessions in the future though...

PCB isn't faulty (Mikes already checked it).

The problem is that even after driving for hours, with the car running at 80+ (using the inline stat), the FBH will continue running when I park up (no idea if its been running the entire time).

I understand it can run on to cool down... but it shouldn't of been on at all if it'd been hot enough for so long
I'll modify the above to suggest that the cut wire be left so it can be reconnected.
__________________
Harry

How To's and items I offer for free, or just to cover the cost of my expenses...

http://www.the75andztclub.co.uk/foru...40#post1764540

Fix a poor handbrake; DIY ABS diagnostic unit; Loan of the spanner needed to change the CDT belts; free OBD diagnostics +MAF; Correct Bosch MAF cheap; DVB-T install in an ex-hi-line system; DD install with a HK amp; FBH servicing.

I've taken a vow of poverty. To annoy me, send money.
HarryM1BYT is offline   Reply With Quote
Old 17th December 2011, 22:41   #24
suffolk boy
This is my second home
 
fiat panda

Join Date: Sep 2009
Location: haverhill
Posts: 6,720
Thanks: 96
Thanked 586 Times in 526 Posts
Default

will do not any harm to solder it back up tho if i pull the fuse will it .or just use bullet connectors?
__________________
fiat panda 1.2 eco
suffolk boy is offline   Reply With Quote
Old 17th December 2011, 23:53   #25
Jakg
This is my second home
 
N/A

Join Date: Feb 2010
Location: Suffolk
Posts: 6,867
Thanks: 0
Thanked 397 Times in 302 Posts
Default

Quote:
Originally Posted by suffolk boy View Post
will do not any harm to solder it back up tho if i pull the fuse will it .or just use bullet connectors?
Thinking about it, if you unplugged the FBH before the T4 the K-Bus being cut would make no difference... AFAIK the T4 can't really do anything with the FBH anyway.
Quote:
Originally Posted by BigRuss View Post
The FBH if the outside temp. is low enough doesn't shut down even when the coolant is fully warm it goes into idle mode

72C = part load operation, anything above 76.5 the control idle mode cuts in, if the temperature drops then drops below 71C it will resume part load operation if the coolant temperature drops further as a result of heavy demand from the vehicle heater the FBH will resume full operation at 56C.

Shutdown proceedure after engine switched off:

175 seconds full load operation, 100 seconds part load.

Hope this helps.

Russ
Thankyou for the info - makes a bit more sense now







After my journey tonight...

When I started the car, it was at 33° C (still warm from my last journey).

It took 6 minutes of driving to get from 33° C to 75° C - I pulled over for a little while and noticed that the FBH seemed a lot louder than usual.

After a ~19 mile journey, the max temp attained was 84° C - it seemed to get to ~79° C quickly, then rise very slowly.

Could this mean my FBH is working properly now? Will give it another test tomorow...
Jakg is offline   Reply With Quote
Old 18th December 2011, 00:07   #26
soapy
Posted a thing or two
 
Rover 75 CDTi Contemporary Diesel Auto

Join Date: Jan 2009
Location: East Yorkshire
Posts: 1,671
Thanks: 18
Thanked 13 Times in 12 Posts
Default

Excellent thread Harry looking forward to recieving my pcb back from frenchmike.:xmas-smiley-004:
__________________
"Quantity has a quality all of it's own"

Joseph Stalin.
soapy is offline   Reply With Quote
Old 18th December 2011, 02:14   #27
Dragrad
This is my second home
 
None * DROWNED

Join Date: Aug 2007
Location: Cardigan
Posts: 33,339
Thanks: 1,257
Thanked 1,664 Times in 1,081 Posts
Default

Quote:
Originally Posted by HarryM1BYT View Post
[note to mods - can this be made an HOW TO please, after a suitable time for any amendments and additions?]

Everyone else - please feel free to report any errors or amendments it might need......

As requested the How to is here. If you amend or add to your OP please let me know and I will update the How To accordingly.

An excellent piece of work Harry

Time is relative so this is the easiest way of doing it :xmas-smiley-004:

BTW

Reassemble reusing the paper gasket by pushing the split back together.

http://techwebasto.com/heater_main/t...hop/63378A.pdf
- This link is dead.....
__________________

Andrew
Ich Dien
Problem solving is... lateral thinking

SEARCH FIRST ...ASK LATER...


Last edited by Dragrad; 31st December 2013 at 02:30.. Reason: update
Dragrad is offline   Reply With Quote
Old 18th December 2011, 17:03   #28
Jakg
This is my second home
 
N/A

Join Date: Feb 2010
Location: Suffolk
Posts: 6,867
Thanks: 0
Thanked 397 Times in 302 Posts
Default

Quote:
Originally Posted by Jakg View Post
After my journey tonight...

When I started the car, it was at 33° C (still warm from my last journey).

It took 6 minutes of driving to get from 33° C to 75° C - I pulled over for a little while and noticed that the FBH seemed a lot louder than usual.

After a ~19 mile journey, the max temp attained was 84° C - it seemed to get to ~79° C quickly, then rise very slowly.

Could this mean my FBH is working properly now? Will give it another test tomorow...
From 1° C -> 75° C took 10 mins this morning... sound like it's working or not?
Jakg is offline   Reply With Quote
Old 18th December 2011, 17:43   #29
HarryM1BYT
This is my second home
 
HarryM1BYT's Avatar
 
75 Contemporary SE Mk II 2004 Man. Sal. CDTi 135ps, FBH on red diesel, WinCE6 DD

Join Date: May 2010
Location: Leeds
Posts: 17,273
Thanks: 2,160
Thanked 2,061 Times in 1,586 Posts
Default

Quote:
Originally Posted by Jakg View Post
From 1° C -> 75° C took 10 mins this morning... sound like it's working or not?

I would suggest that it is working. Maybe check to see if the FBH's flue is hot to be sure?

Mine running is very obvious, I can actually see the needle on the temperature gauge rising as I drive.
__________________
Harry

How To's and items I offer for free, or just to cover the cost of my expenses...

http://www.the75andztclub.co.uk/foru...40#post1764540

Fix a poor handbrake; DIY ABS diagnostic unit; Loan of the spanner needed to change the CDT belts; free OBD diagnostics +MAF; Correct Bosch MAF cheap; DVB-T install in an ex-hi-line system; DD install with a HK amp; FBH servicing.

I've taken a vow of poverty. To annoy me, send money.
HarryM1BYT is offline   Reply With Quote
Old 18th December 2011, 18:47   #30
Jakg
This is my second home
 
N/A

Join Date: Feb 2010
Location: Suffolk
Posts: 6,867
Thanks: 0
Thanked 397 Times in 302 Posts
Default

Exhaust (flue?) is hot (or at least it was even before it was working properly!)
Jakg is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 09:15.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd