Just came home with a 1998 Audi A6 2.8 Quattro, got it for a steal at $1300 cash, car does need some minor work.

Here is my problem:

-ABS light is always on, red brake warning light is flashing.
-Brake lights do work, but when I turn on the headlights, the stoplights stay lit up and do not turn off!
-Push the brake pedal and there is an annoying chime.
-Also, I noticed that the front right signal marker lights up when I push the brakes.
-Warning message on dash - brake light out.

What could this be? Previous owner had put the wrong bulbs in the taillights, I have since fitted the correct bulbs and the problem still persists.
I searched around and have read that it could be the brake light switch. Any other possibilities, also anyone els have this issue?

 

Well the brake light light switch would be the first and easiest thing to do. If that doesn't work its time to invest in a vag com. www.ross-tech.com. When you have that in hand try to communicate with the brake electronics, if you can't the ABS module is toast, which is pretty common.

 

Thanks for the fast reply. I already tryed a new switch and it didn't work.

Can I unplug the module for diagnostic purposes? I am going to invest in VAG-COM.

 

Unplugging the module won't be of any use, however you can inspect the pins for corrosion. Once you get your vag com you can diagnose just about anything.

 

The switch I tried was from a 2000 a6 and it seemed to be different. Are they supposed to be different?

 

Different how? Different color? No, they should be exactly the same, and they are VERY easy to break.

 

Here is a picture of both(clink link) mine is the 2 prong one the one i grabbed out a 2000 2.8 a6 was a four prong. To my knowledge I thought they were all the same. Should I pick up a new two prong? or do my problems sound like they are not brake switch related? Any input would be great. Thanks guys.

http://www.ecstuning.com/Audi-B5_A4-...aign=postreply

 

Well you need the right switch for sure, there are A LOT of systems that use the brake switch signal to operate things. Cruise control, ABS, transmission, ECM etc. If the signal isn't right all kinds of wierd stuff can happen. Get the correct switch.

 

Ok cool will do I will give another update tomo after I install a new CORRECT switch... Any alternative place to get one besides Audi? How much does Audi want for one? Thanks again

 

Ok, I picked up a new brake light switch and it does not seem to make any difference. To review my symptoms again:

-Brakes lights stay on when headlights are ON.

-When I hit the brakes with the headlights OFF they seem to work fine EXCEPT the passenger side front signal light turns ON as well.

-When I hit the brakes with the car off there is a a continuous chime/tone when I have my foot on the brake.

-The dash also shows a picture of a bulb with an "X" through but I have now bulbs out.

-Also the ABS light is on and the BRAKE light is blinking.

I have another ABS module from a donor I can put in but, I do not think that all these problems would amount from a faulty module(I could be wrong).Any input would be much appreciated. Thanks again.