WEBASTO FBH DIAGNOSTICS update
 

WEBASTO FBH DIAGNOSTICS update

-Engine cold and stopped

-At first, unplug then replug the power connector (or fuse F8) in order to reset the system.
-Connect permanently Pin 3 to earth. (To + batt in case of older model)
Simultaneously start a TIMER and listen when the fan stops

IF stop after 3 sec, restart 4 seconds later and finally stop at 2 minutes 7 sec;
An error is generated; may be caused by:

-Battery voltage lower than 10 volts
-Glow plug open or short circuit
-Circulation pump open or short circuit
-Fuel pomp open
-PCB defective (send me a PM)

IF a weird turbine noise appears at a door opening e.g.,PCB likely faulty.

IF stop after more than 2 minutes 10 sec, then
PCB and all devices are good (except doubtful glow plug)

IF stop at 4 minutes 5 sec, Glow plug resistor too high (0,6 ohms for instance),

IF stop at 4 minutes 40 sec it is a ignition fault, (fuel pump priming fault e.g.)

Mike

Hi Mike. May I tap into your grey matter for a bit please.

My FBH has been working fine up until recently. I haven't heard it come on when outside temp is below 5deg C. Also last night when I manually fired it up from the Webasto timer she ran for a while then shut the pump off and sat idling for ages. Tried her again and after firing up the fan went into what can only be described as overdrive. Then again shut fuel off before idling.

I've not heard of this before!

Tried the FBH this morning and it ran fine for 10 mins.

I'm wondering if I'm developing a fault or I just had a magic blip.

Also I must add that at the same time my sat nav spat out it's disc! Related or not I don't know. Engine was off both times while I was waiting for my daughter.

Any help or advice from your good self will be graciously received.

Many thanks and kind regards. Steve.

Sure mine is not running right Mike, I will run the test at the weekend

Hi Steve,

If it is able to run more 5 minutes, everything is all right !
But be careful,if the battery voltage fall under 10 volts(engine stopped)
then an error is generated followed by a shut down.

Mike

Hi Tony,

In case of any doubt about your PCB,send it to me;
I make an overall check on my test bench and,
you pay only if there is a fault and i can repair it.

Mike

My fbh decided to wake me up yesterday! It made a loud BANG as I set off! Followed by two more stifled sort of backfires, so I pulled over, checked it, it seemed to be running as it should. :shrug: So I continued my journey with no more problems or noises.. :bowdown:

Maybe it was annoyed at being disturbed innit.. :D :D
...

Hello James ,

Normally ,to avoid that,it is the role of the the burn out fonction when you stop it
.
By chance,did you stop it the day before by removing or disconnecting the

fuse or the power ?

Mike

Hiya Mike.. :)

Nope, I made a short 8 mile each way trip the day before with nothing unusual happening.. The burner cut in on the first trip as it was colder then, but I doubt it fired up during the return as the engine was still slightly warm.. :}

I'm off out again shortly... To bang or not to bang.. That is the question.. :D :D :D

But I think the temp is above 5c now so the burner wont need to get out of bed.. :) ;)
...

At least , it proves that your glow plug is well alive !:)


Mike

Thanks Mike. That's reassuring. I've never heard it do that before and the fan did waver in pitch. I shall keep an ear to it. Unlike James bless him. That FBH sounds like it's from Dads Army :D

Regards. Steve.