Hello All:

Before I proceed to asking my question, I'd like to than "Silver D2" and "Torsion's A8" for their expertise / advice in helping me diagnose and fix Brake light switch issue I had with my 2005 A8L.

Well, good news is I purchased a new Brake light switch from dealer for $15, and it took me about 45-minutes to remove under dash cover & replace brake light switch. After successfully installing brake light switch; now I have "AIR BAG LIGHT ON!!! - Can't seem to win these A8's (LOL).

My question to all you experts out there: How do I diagnose / fix this problem?

I made sure every connection (brake light switch, Ignition, under dash light, OBD II scan socket (X2) were ALL securely connected back. But I don't know why the AIRBAG LIGHT IS ON!

**I hate to go to my local dealer because those guys ripped me off two years ago when I had an issue with my motorized trunk lid not latching. Those "freagging" jokers told me I needed the motor and hinges replaced; and paid them $1800. Well.... after paying $1800 the problem did not go away, and it turn out ALL I needed was a new latch for $105.

Any ideas, suggestions and comments with AIRBAG issue will be much appreciated.

Thanks in advance guys! - All of us here on the forum do value ALL of your invaluable expertise and advice.

 

You'd really need to read the OBD codes...that should help pinpoint the problem. If you don't have a code reader or Vagcom, Autozone & Advance will do a free scan...not sure, but it should be enough to give an airbag code that will describe what part of the system is at fault.
I don't have a manual on your year car, but do through 2003 models...the airbag control module on those models is close to where you were working...on top of the central tunnel ahead of the shifter, with the wiring entering the rear left above the gas pedal. If it's there on your car, maybe dislodged something(?)...also air bag connectors under every seat...maybe a yellow connector...if you pushed anything under the seat(?)
Anyway, like I said, codes should show on OBD for airbag problem.
Good luck.

 

As always thanks Silver D2. I will take the under dash off again, and see if any of the wiring you described is pinched. But first, I'll drive down to AutoZone to see if I can have them scan and tell me the exact error code for the "AIRBAG" light!.

 

My best guess is when you took the knee panel off you didn't reconnect the airbag connector to the knee airbag. There is a small silver box located on top of that panel which is an airbag for your knee caps, it should have a small yellow connector. Other than that check the fault codes.

P.S. The dealer changing the trunk hinges and latches WAS necessary per audi TSB (something something don't know the number) but they should have known to diagnose the latch as well, thats just poor diagnostics by the tech.

 

Dear Auditech79,

Thanks! I took the panel down and made sure the yellow conectors (A) hooked to the OBD-II diagnostic slot and (B) another yellow connecter on the "under panel" itself with a silver cylinder - which I'm guessing is the AiRBAG.

Both (A) and (B) are securely connected. The ONLY thing I can think of is when I took the old brake light switch out and was using it as practice to properly replace the NEW one; I started the car accidentally without the brake light switch harness connected.
At the time the AIRBAG, ABS light came on, but when I placed the NEW switch, the ABS light went off but NOT the AIRBAG.

* Quick question: So, if the was TSB Bulletin to replace the hinges - why did the dealer charge me $1800? A few months ago there was a TSB with ignition coils, and they replaced it for FREE; but they charged me $1800 for trunk hinges! --which did not fix the problem anyway.

Thank you as always. I suppose I'll have to take it to the dealer to have whatever code clear, because all wires are securely plugged-in!

 

Unfortunately, there is a big difference between a recall and a TSB.

The ignition coils (at least on mine, and it sounds like yours too) were replaced under a safety recall, and yes that was free to me.

A TSB is another story altogether. A (T)echnical (S)ervice (B)ulletin is just a recommended repair for a known problem. Just because there is a TSB does not mean that the repair is warrant-able.

I have even seen a TSB that required an adjustment. Adjustments for that manufacturer were only covered for 12 month or 12,000 miles, just like wear items. Outside 12/12 it was customer-pay.

Like it or not, there it is.