replaced my comm unit now airbag light on permanent

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

Moderator: Moderators

Post Reply
boab
1.8 8v
Posts: 42
Joined: Tue Oct 20, 2009 9:27 pm

replaced my comm unit now airbag light on permanent

Post by boab »

Hi ive replaced my comm unit and now i get beep with display showing airbag fault and light is permanently on,any ideas of what this can be?thanks
User avatar
steve_earwig
Moderator
Posts: 19812
Joined: Thu Oct 04, 2007 6:09 pm
Location: Jastrebarsko, Croatia http://www.jastrebarsko.hr/lokacija/

Re: replaced my comm unit now airbag light on permanent

Post by steve_earwig »

Argh!! :( That's a bit of a barsteward. Three things spring to mind: Check the connectors under the seats, they're the most common problem and it'd be a pig to take it all to bits again to find it was these. If they're ok then it must be something to do with what you've been up to. I'm afraid you'll have to take it to bits again to check the connectors, on the airbag, on the unit itself and the ecu under the center console. It might be enough to just reseat them (take them apart, put them together again) but check for bent pins or any other sign of damage. It's not that I think you're a ham-fisted clod - I've done it, they're sodding fiddly! Lastly, there's always the possibility you've picked up a duff'un - where did you get it from?
Unskilled meddling sin©e 2007

The submitted form was invalid. Try submitting again.
boab
1.8 8v
Posts: 42
Joined: Tue Oct 20, 2009 9:27 pm

Re: replaced my comm unit now airbag light on permanent

Post by boab »

cheers for reply i got comm unit from breakers it never had this problem before so im presuming its been me fiddling about in there,never moved the seats as they are electric and battery was disconnected for more than an hour,only difference i saw was my cars a 02 plate it had a 2007 com unit fitted before i purchased car.The car i got it from was a 2003 model exactly the same connections and has the same auto lights/wipers maybe thinking about the airbag connections if i have put the plugs in the correct side of airbag???? have to check and see
boab
1.8 8v
Posts: 42
Joined: Tue Oct 20, 2009 9:27 pm

Re: replaced my comm unit now airbag light on permanent

Post by boab »

right replaced comm unit with new one fault was with old unit for abs problem,But i began to replace this comm due to problems with headlamps,now and again headlights do not work on dipped and now they do but stay on with key removed,i have to disconnect battery to get lights off and my central locking wont work with key tried numerous times to prog key with no joy.do you think this can be related to bsi?ive done a bsi reset but still problems.everything else works perfectly,its just headlamps are continously on dipped with key removed and othertimes when switching from sides to dipped the dipped lights go off,and the other times the dipped beam when switched on flash on and off few times before staying on,getting annoying now just glad its getting lighter earlier now to save relying on lights.any help appreciated.is there anyway to check bsi unit myself?if so what diagnostic tools will i need.thanks
bangernom1cs
2.0 16v
Posts: 182
Joined: Wed Jul 09, 2008 4:00 pm

Re: replaced my comm unit now airbag light on permanent

Post by bangernom1cs »

I had to get a new com2000 (Valeo/Dav) unit this week as the MOT/council test failed it.
I used Neat Autos who are on eBay and got the correct one for £125 overnight.
It looks as though its the 3rd one on the car according to the date stamps.
I looked on the Knowledge base and thought twice about doing it myself!

But what a shameful waste of money having to buy the whole lot instead of just a plug in stalk like on the D8's

T
User avatar
steve_earwig
Moderator
Posts: 19812
Joined: Thu Oct 04, 2007 6:09 pm
Location: Jastrebarsko, Croatia http://www.jastrebarsko.hr/lokacija/

Re: replaced my comm unit now airbag light on permanent

Post by steve_earwig »

And early D9s :evil: I've heard of some needing much more than three, maybe we should pretend they're bimmers...
Unskilled meddling sin©e 2007

The submitted form was invalid. Try submitting again.
boab
1.8 8v
Posts: 42
Joined: Tue Oct 20, 2009 9:27 pm

Re: replaced my comm unit now airbag light on permanent

Post by boab »

forgot to update this thread so incase anyone has similar faults with lights etc it was down to my engine bay fusebox damp and shorting,10min fix.
User avatar
steve_earwig
Moderator
Posts: 19812
Joined: Thu Oct 04, 2007 6:09 pm
Location: Jastrebarsko, Croatia http://www.jastrebarsko.hr/lokacija/

Re: replaced my comm unit now airbag light on permanent

Post by steve_earwig »

Splendid! Glad you got to the bottom of it & thanks for the update :cheesy:
Unskilled meddling sin©e 2007

The submitted form was invalid. Try submitting again.
FarmerPug
2.0 HDI 110
Posts: 9656
Joined: Tue Jun 01, 2010 5:42 pm
Location: The Countryside, Northern Ireland
Contact:

Re: replaced my comm unit now airbag light on permanent

Post by FarmerPug »

you get the feeling that the com2000 unit isnt well liked amongst us 406 oweners, even to the point where a guest to this site would think the com2000 is a bad thing.
User avatar
steve_earwig
Moderator
Posts: 19812
Joined: Thu Oct 04, 2007 6:09 pm
Location: Jastrebarsko, Croatia http://www.jastrebarsko.hr/lokacija/

Re: replaced my comm unit now airbag light on permanent

Post by steve_earwig »

That might be because they're rubbish... Not all of them though, it seems to be mostly just the ones for cars with rear wash/wipe because they came from a different manufacturer.

Still, if you read these forums you'd think the 406 is a disaster area through and through, you just have to remember that the vast majority of owners never find this site because they never have any problems!
Unskilled meddling sin©e 2007

The submitted form was invalid. Try submitting again.
FarmerPug
2.0 HDI 110
Posts: 9656
Joined: Tue Jun 01, 2010 5:42 pm
Location: The Countryside, Northern Ireland
Contact:

Re: replaced my comm unit now airbag light on permanent

Post by FarmerPug »

Only joking with you i know full well they are rubbish, hopefully this one i got off ebay when i bought my car is the improved version. But apart from that i think the 406 although it has problems is a good car and most problems ive had seem to be confined to electrical issues with some being caused by me. I like a car with the odd problem theres a certian satisfaction of fixing a problem that an audi driver will never experience.
Post Reply