It's good to hear from other people who have the same problem. I really think, flushing brake fluid is a key point here and re-seating the connector of the ABS module. I've done that, and have no problems anymore. If brake fluid is old/dirty, I'm pretty sure this is a cause of a problem. There is an uneven pressure distribution in the brake lines. The ABS controller might be going "crazy" when sensing that "bad" pressure, due to clogging for example. The Dot4 fluid is prone to moisture absorbtion. If the car is driven in wet climat, the fluid should be fully replaced every 2 / 3 years.

If there is no ABS light showing on the instrument cluster, there is no need for rebuilding of the controller. Thorough flushing should be enough.

Also I think, there might be a software glitch/bug in the firmware of ABS controller or ECU. I know Audi was upgrading firmware of the ECU to correct some bad transmission shifting. Not sure about ABS. This would be a good question to ask a dealer.

 

Here is the strange part .. if you only have ABS there "should" be no way for this to happen as the function of the ABS is to have a pathway for fluid to flow in a lockup situation so the caliper will release with your foot on the brake. providing a wastegate sort of thing . i can't see how it puts the brake on in normal driving. If you have the ESP option then maybe I can see this as it will apply different brakes to stabalize the car .. I do not .. which is wierd ..

 

I finally got the car back, and his decision was to do nothing. A few codes came up,but he felt they may be old , so he cleared them. He wants me to wait and see if it happens again ,and if it does he said to put the car in neutral and try to roll the car to see if the brakes are locked. Even though I already told him that it was the front right passenger wheel. I asked him to flush the old brake fluid out but he wants to wait. I did have the abs controller connection cleaned out as u guys suggested. I'm not going to switch mechanics just yet cause he is one of the better audi techs around here. I will post the codes soon.

 

Why wouldn't he want to replace the fluid? I would switch mechanics immediately. Excuse me here, but is this mechanic a dump a$$? Wait 'till it happens again? Wow. Flushing fluid is not a big deal. It takes about 1 hour. It saves the ABS pump, improves braking performance. Good brakes save life.

 

Thanks A6 for reassuring me that I'm not the only one thinking that. I really and truly don't want to wait for a problem to come back around, cause there is too much at risk. The lines will be flushed by another mechanic, cause I can't wait. By the way I will get the codes posted soon.