No connection with airbag controller

[Kroegarn]

Since the first of January 2012 there is now a MOT failure on a lit or not properly lit airbag dash light. Mine have been shining so bright since I put a bulb in there back in -04/-05 something, but just now resulted in a failed MOT .

The big issue is that I can not get any connection with the airbag controller. The other controllers (ECU, ABS, Aircon) works fine in my VCDS-Lite 1.1 (some kind of china copy cable is used).

Any ideas on how I should go about this? Replacing the airbag controller unit? One quick fix that I would like, is some sort of timer relay that will light the bulb up for a couple of second upon ignition. But where can one of those be sourced?

[rj scotty]

The airbag controller can be a pain to establish coms with. I a have a usb cable that won't connect to airbag controller at all and an rs232 cable that works a fine with airbag.

If your using usb then I would suggest buying or borrowing an rs232 lead. If one wont work work with a certain controller its almost certain the other one will.

[Kroegarn]

The airbag controller can be a pain to establish coms with. I a have a usb cable that won't connect to airbag controller at all and an rs232 cable that works a fine with airbag.

If your using usb then I would suggest buying or borrowing an rs232 lead. If one wont work work with a certain controller its almost certain the other one will.

Hmm interesting idea, although there are'nt many laptops with RS-232 on them anymore. Even if I would get my hands on a RS-232 cable I´d still would have to use the RS-232 to USB converter to connect it to the computer, which sounds as if it would defeat the purpose? Unless it is the manufacturer of the cable that matters?!?!

Feels like that the first step now will be to put it all together and try my local dealer to see if they can retrieve any error codes.

Cheers

[Kroegarn]

Went by the local mechanic with some cookies and their equipment had no problems getting the fault code out. So my "china" copy does not cut it, when comes to the airbag controller. Anyway the errorcode stated something like "faulty driverside airbag igniter".

rj scotty: you were correct, tnx for the hint.

Will now try to get hold of a 2,7ohm resistance "thingy" to hopefully fool the airbag controller that it is connected to a fully functional airbag.

[Wheeljack]

Good info...I've been having issues connecting to the airbag module in my new 93 urs4. I'm also using a cheap ebay USB adapter and VCDS.

Because it connects with the other modules, I blamed it on the airbag module. So I ripped apart the center console and switched it out. Same outcome. Then I blamed it on the wiring somewhere, but figured it wasn't worth the hassle to me yet.

Now I've got something new to try to get the dreaded light out, before I punt and pull the bulb.

Thanks RJ!

On another note, does the airbag light indicate the specific issue through the way it blinks? Mine blinks for about 15 seconds or so at startup, and then is constant on. I've not been able to find anything on if that is trying to tell me something specifically.

[5cylinderman]

The only way I could communicate properly with my airbag controller in a '95 C4 tdi Avant was to buy a 5metre RS232 cable and use an old version of Vag Com from my home PC. I had to get the car close to my office window though!
RS232 will work but my USB cable had no hope with Airbag system.