I recently bought a 2003 Audi A6T for what I thought was a good price. Two months ago I put it in the shop with ABS, Check Engine, ESP lights on. After 3 weeks the relaced the ABS module $600.00 the Master Cylinder $300.00 cleaned the MAF 150.00 and changed the transmission fluid $200.00 after 3 weeks I picked the car up all lights still on and had to pay to $1350.00 get my car (he did not have the software to reset the codes). Took my car to another mechanic a month ago same issues and I noticed a leak from under the car.

New mechanic replaced MAF, replaced water pump, replaced timing belt, relaced cam gaskets and seals, replaced head cover gaskets $ 2200.00. I am really anxious for my car its been a month, mechanic says I need a steering angle sensor additional cost because all lights stay on for the steering anlge sensor fault. Car has doubled what I paid for it and I only drove it 1 week in the two months I have owned it.

 

ABS + ESP lights both ON and you either has all brake lights on or all off.
A simple fix ... part cost $12.55 replace the brake pedal light switch ... I did it myself.

VW has it recall but Audi didn't do the recall. It is little tricky when install the new one.

VW's installation
VWVortex.com - DIY - Installing a new brake light switch (without breaking it!)

The new brake switch insert into position & DO NOT touch or push the brake pedal. Just leave the pedal in its original position.

Audi switch when fully inserted & rotaed to click into place, note the connector is in south position, not as VW's one in north position. Just the opposite.