HI all,

noob here and sorry to have a first post as 'help' but my fiesta has just started playing up with a weird problem.

Was about to take my kid to school as normal and the car alarm started to go off. Pressed the key fob and it switched off. All good but then it happened about 10 more times after this with me using the key to stop it. It finally stopped going off but now the following wont work

Central locking

Hazards

Indicators

rear wiper

and the intermittent front wiper

Also, the rear window heater seems to be on all the time and wont switch off! Front screen heater wont work

It drives fine (!) apart from all this.

Anyone got a clue what the problem is. I'm thinking about disconnecting the battery for a bit to see if it clears it but the fact that some bits are not working makes me think that the problem could be quite bad!

 

Thanks, sorry again for the first post being a help one!

is this 2007 fiesta as shown under you ID?  is it a built in ford alarm? (I think most fiestas then did not have an alarm as standard).

Is it a later fitted alarm of different make?

If I was in your position I think I would disconnect the battery(like you say) and pray.

Do you have your radio code to tap into the radio when you reconnect battery?

Hi, thanks for the reply

Its a Laser line alarm. No idea when it was fitted i'm afraid. Yep, i have the radio code and it does ask for this when the battery is disconnected

I left the battery disconnected overnight hoping it would clear and just reconnected it and the problem is still there.

I've spent hours on google trying to look for some indication what could cause this is and my problem appears unique (which is not a good thing). For example, how can the intermittent front wipe not work but push the stalk up to 'regular' wipe and it works!

There are a few comments about it being ECU related but i've spoken to 2 mechanics and they are stumped as well!

 

1 hour ago, bluejam said:

how can the intermittent front wipe not work but push the stalk up to 'regular' wipe and it works!

There are a few comments about it being ECU related

It will not be ECU related, but it could well be the BCM (aka GEM). This module is separate from the ECU, and controls all body related functions like wipers, de-misters, lights, locks & doors, etc. It is possible the normal speed wiper position is hard wired from switch to wiper relay, but the intermittent will certainly go through the BCM.

It does sound a bit like the alarm system has malfunctioned, and taken out a fuse that powers a large part of the BCM. I don't have the Fiesta fuse list to hand, but could probably dig up the manual if needed.

Another possibility is a bad contact in a connector to the BCM, that first upset the alarm, then stopped the BCM from working. Door ajar signals etc will all go both to the alarm and to the BCM.

The worst case is that the BCM has been internally damaged in some way. But I would suggest that all other possibilities are carefully investigated before making this assumption!