Oh No

[Rufras]

It never rains but it pours, why so soon before Christmas?
A couple of days ago tried my FBH (Webasto)and it would not start where four weeks ago it was fine. Tonight I went to leave in the car and the ‘bonnet open’ sign on the dash but bonnet closed. I wondered if trying to fire the FBH it had upset the electrics?
I disconnected the battery for a couple of hours hoping for a reset but now the following do not work:-
-Aircon no longer works and just displays ‘er’ both sides and is berserk.
-Indicator telltale on dash no longer functions.
-Alarm stopped!
-Central Locking has disappeared
-no heated rear window
What has gone wrong

[Christopher]

Looks like a BCU problem or something - don't know how to try and diagnose that though at this stage ... my first reaction would be to disconnect the battery - but you have already done that! Have tried briefly resetting the battery now - ie disconnect for a minute or two rather than a few hours??

[Rufras]

Initially I disconnected the battery for one minute which gave the same effect as disconnecting it for an hour.

[Christopher]

If it was me (and thats because I like fiddling!!) I would find the BCU - somewhere under the glove box I think - and reseat its connectors - just unplug and plug in again WITH BATTERY DISCONNECTED and then try again .... I don't know what else to try at this stage :(

[Lovel]

It never rains but it pours, why so soon before Christmas?
A couple of days ago tried my FBH (Webasto)and it would not start where four weeks ago it was fine. Tonight I went to leave in the car and the ‘bonnet open’ sign on the dash but bonnet closed. I wondered if trying to fire the FBH it had upset the electrics?
I disconnected the battery for a couple of hours hoping for a reset but now the following do not work:-
-Aircon no longer works and just displays ‘er’ both sides and is berserk.
-Indicator telltale on dash no longer functions.
-Alarm stopped!
-Central Locking has disappeared
-no heated rear window
What has gone wrong

Corroded or poorly connected battery terminals?

[Mike]

Hi Rufras :)

sorry to hear of your troubles :( If you have no luck then it's worth checking the earth straps as if you have a loose earth then that would cause these sort of issues.

hth

Mike

[raykay]

The common factor is the K-Databus, remove the plug on the FBH, the front one, if everything else returns to normal, that's where the problem is - but i'm afraid I can't help with a remedy!

[Simon]

Just posted a reply on mg-rover.org forums. Here's the post again tho:

Problem could also be a flat battery (or at least not holding sufficient charge to support the cars electrics).

There have been many-a-story told that cause havoc to the cars electrics when the battery (although it may not be totally exhausted) is not providing enough current consistently.

What does the "peep hole" on the battery indicate? If possible, also try another battery (brand new if possible) to see if that cures your problems.

If not, it may be a case of getting a garage to put it on testbook. Ask the garage to give you a print out of the error codes and then come back on here and tell us what the error codes are. Often simple things that can be fixed by yourself will be the cure. Don't let the garage say you need such-and-such replaced at £XXX until you get a second opinion from all the knowledgable people on this site! http://forums.mg-rover.org/images/smilies/wink.gif

[GreyGhost]

First class advice Simon

I would have said start with a good known battery before looking elsewhere.

[Rufras]

I've got the electrics to behave normally by unplugging the front connector to the FBH. It appears that the FBH must be at fault because everything else runs normally when this is unplugged. The FBH when tested just spins the fan for a few minutes then hums and start lock-out when tested. Its is annoying because this ran fine two weeks ago.
The only thing I think is maybe the control pcb on the FBH but I am open to ideas!

[Simon]

Being a KV6 owner I've not got any experience on FBH's.

I think I recall from the mg-rover.org forums tho that a faulty FBH can send weird signals through to the cars K-BUS, therefore causing things to go all a bit wierd. However, don't quote me on that as I may be wrong! :rolleyes:

Hopefully Keith or someone with FBH experience will be able to shed some more light on your problem...

[Keith]

Any device that goes berserk on the bus could cause odd behaviour
I am surprised the FBH was on the money first time that is very lucky!

Does the fault definately return when it is reconnected?

My posts re the FBH on .org were re odd intermittent startups on a couple of cars when the doors were opened that was all

In this case there is perhaps one or two problems the FBH will not run and the FBH may be causing bus errors. the FBH needs testing on Testbook or by following the trouble shooting guide I posted in the How to section in the meantime the FBH can be reconnected minus the K bus (Red White Yellow) wire if necessary.

[Rufras]

Yes, when the FBH is connected all goes haywire again, aircon err messages, boot opening, no central locking, etc. Checked with Webasto and new control PCB comes as part of assembly and £334!

[Keith]

Plenty in the breakers and ebay Germany plus 2 CDTs being broken on ebay at the moment.

[Rufras]

Got several from a breaker, all of them with the same fault (not pulsing the pump) and in various sad states. Finally I bought a new FBH and find that Rover were selling them cheaper than if I had gone to Webasto, £386 all in! Tested it and it is fine with everything working well. I have now concluded that these have a limited life and you have to buy new. Watch out for Ebay their Webastos are dearer than anybody elses.

[Jules]

Yes, when the FBH is connected all goes haywire again, aircon err messages, boot opening, no central locking, etc. Checked with Webasto and new control PCB comes as part of assembly and £334!

I had identical symptoms to these after washing a 54 Plate CDTi AUTO !!

NON SAT NAV MODEL & NO CD CHANGER FITTED BUT DOES HAVE A TOWBAR

Symptoms were intermittent though and got better the next day.

This car had a Towbar and single electrics fitted BUT DID NOT have a Webasto fitted but it did have the timer all on it's own in the centre console! I removed the timer the night before the fault (diesel heater must have been removed by previous owner)

I replaced the heater control panel just for elimination purposes but the fault never re appeared so this case was inconclusive.

Keith suspects I disturbed the "blue header" multi connection behind and the heater console. I phoned the new owner 2 months later and he says the fault has not re appeared. :confused:

[simpsora]

The common factor is the K-Databus, remove the plug on the FBH, the front one, if everything else returns to normal, that's where the problem is - but i'm afraid I can't help with a remedy!
Hello,
raykay 'on the money again' .There are now more and more of these webastos displaying the same fault ( k-bus gone crazy).Usually means webasto no longer giving output pulses to webasto pump (this problem has been investigated by several experts on the forums, including Rover-Ron).I don't think this is now confined to one or two webastos , indeed I think they will nearly all get the same fault with age . Possible tidy profit to be made for anybody that can pin point what component(s) goes wrong on PCB board and can offer repair service!!

Just my opinions,
Regards , Robert.

[raykay]

My FBH went haywire with the K-Bus, disconnected the K-bus cable at the heater and everything worked. It doesn't need a K-bus connection to work as it is only there for diagnostic purposes - cheaper than a new heater!

[Jules]

Still doesn't explain why I had the same various fault symptoms but with no FBH fitted:confused: