One problem related to brake abs warning light has been reported for the 2000 Audi A6. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2000 Audi A6 based on all problems reported for the 2000 A6.
Abs/brake light started flashing infrequently and I called maplewood Audi service and they proceeding to tell me it was a brake light switch, through further investigation I found that this is a very common problem with their abs control module and it is a "factory only" fix because of reprogramming and such and it would run about $2000. I belong to a couple of Audi forums and this is one of the most common problems. I don't see how this proprietary system is allowed to continue without accountability by the manufacturer and or dealerships. Unlike their other poor practices for monopolizing service to these cars this one affects braking and thus safety.