citroen c8. heater blower, sliding door, airbag and other faults

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edenboy-ragit
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Joined: 09 Feb 2016, 09:45

citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

hi all.
ive been repairing a 2003 Citroen c8 2.2 hdi that i brought cheap.
i have so far repaired engine issues. and now runs & drives ok.
im still having a few problems!
the 3 sunroofs were all leaking and was abit of a swimming pool in the car! after several days attempting to repair the sunroofs i ended up sealing them all up to stop the water pouring in!
this water has caused havoc with the electrics!
1) the drivers rear sliding door is not working. press the button, bleeps once, unlocks but motor doesnt open the door! i tested motor, works perfectly, replaced ecu and still same problem. also have tried a reset but no luck, also fuse tested. what else could be faulty and causing this issue? thinking maybe the door lock or handle? any help would be good.
2) heater motor not working, the controls freeze up. have checked connection to motor but not causing the issue. suspect maybe blower motor has failed. how many motors are fitted to this blower system?
3) airbag fault. unable to communicate via obd port to ecu. had ecu checked and no signs of damage. where are the fuse for airbag ecu? which wires to the airbag ecu supplies power? i want to test for power 1st before i replace expensive ecu.
few other issues, handbrake warning light on whilst driving, maybe just switch, after just need tracking and tidying up!
any help right now would be great.
cheers lee
edenboy-ragit
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Joined: 09 Feb 2016, 09:45

Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

just done a scan of another ecu on the car. has a fault:
Airbag control unit, Datab line communication faulty - present
any ideas what could be causing this?
also unable to get rid of handbrake fault, removed wires and connected together still the light remains!
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GiveMeABreak
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Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by GiveMeABreak »

Read this post for the Door issue: and underneath there is a video on the whole system (a bit long, but bear with it as it does cover the internal mechanics too)
http://www.frenchcarforum.co.uk/forum/v ... hp?t=52216
https://www.youtube.com/watch?v=c5dn6kS ... vid%C3%A9o
The heater problem is probably the resistor pack if it's gone non-responsive.
edenboy-ragit
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Joined: 09 Feb 2016, 09:45

Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

ouch my head hurts! lol
the video was informative but no english! lol yeah im sure the motor and ecu are ok but think the problem is probably with the switches in the doors. i have noticed my doors do not open from the outside handles and the one im having issues with doesnt open from inside handle!
bloody french cars and there electronics.
the heater blower i measured 14v (engine running) to the motor so still want to have a proper look at that really before i decide what needs replacing!
still undecided about airbag ecu issue as that video showed a link between airbag ecu and the sliding doors!
cheers lee
edenboy-ragit
Posts: 8
Joined: 09 Feb 2016, 09:45

Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

anyone have any ideas on the airbag ecu issue?
anyone know what the data b communication line is? could it be a faulty ecu?
how do i check ecu for 12v live feed (without blowing all aitbags up) lol
edenboy-ragit
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Joined: 09 Feb 2016, 09:45

Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

just wanted to update this for other people's reference (as i know what its like reading a post with identical problems and being no solution)
the heater blowers: as i said i was getting a good positive and good earth to the motor but wasnt running. replaced motor (not a DIY job, im a mechanic and stuggled for hours especially on the top bolt)
the rear sliding door: as i mentioned earlier post i made sure the motor worked (swaped the doors over on the ecu and tried opening other door) i changed the ecu and still problem remained. checked wires and fuses. i brought a replacement door lock (has a micro switch to tell the ecu the door has been unlocked so the ecu will start the motor) this was a relatively easy job for a competent person with the correct tools (T30 torx bit, drill, rivet gun and axle stand to hold the door)
so far no joy with airbag ecu or handbrake switch, will probably end up buying another ecu.
will keep updated. hopefully someone may comment with another idea with the airbag issue???
Simon10
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Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by Simon10 »

Hi, was it a faulty door lock? I have an issue with the door. Mine will unlock when pushing the button, moves about 2” then stops and beeps. I tested the micro switch on the lock and it seems fine
edenboy-ragit
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Re: citroen c8. heater blower, sliding door, airbag and other faults

Post by edenboy-ragit »

Yes the door lock was at fault.