Fashizzkes84

ok, so here is the issue. last year i had a small problem which led me to believe that i had to change my real wheel bearing. and so i did. what i didnt realize was that in order to change the bearing i would need to remove the rear brake pads, which in turn would mean using a vag-com vcds to retract the parking brake for service. i did the repair and forced the pad and caliper back to place without the use of a vagcom vcds. didnt realize the proper procedure until after i did it. so, therefore parking brake malfunction light has come on. i finally got sick of seeing the parking brake malfunction light and purchased a vcds vagcom hex-can usb from rosstech and attempted to repair the problem. after retracting the parking brake and finishing replacement of the rotors and rear pads, the parking brake malfunction light remained on and the parking brake light is blinking. also the (brake) light is also visible on the dash. i would greatly appreciate a very experienced audi personel to offer proper information on resolving this matter. thank you in advance. 06 a8 71k miles

Mister Bally

Try opening the brake caliper properly using the diagnostic software and vernier caliper to measure and set pad thickness. I have had to do this twice one of the times I replaced my rear pads. If that desn't work, there is probably a fault code you can read that will tell you that the brake caliper is defective. You could have ruined it if you forced it back to get it off along with the brake pads. In that case you will need to replace it.

mishar

Welcome to the board!

If your rotors doesn't have lip you can remove and assemble back rear caliper without VCDS. Only that should not cause any faulty codes. Disconnecting harness and moving piston would. I am not sure what exactly was that "forcing". You can't push the piston in without braking something. You can unwind parking brake by removing the motor and manually rotating, or by rotating piston. If you did that and didn't wind it back into place you will get the code since calipers would be out of synchronization. Can you describe better what exactly you did while replacing the bearing?

MP4.2+6.0

It might be you just need to recalibrate, or you may have broken something internally. As Mister Bally suggested in general, try opening and reclining it, and going through the pad calibration procedure. I have had to go it a few times of and on before it would finally settle down. If/assuming you are using a laptop, do not let it go to sleep on the power settings while doing it; my own experience suggests if laptop goes to sleep mid calibration it may not work right.

Fashizzkes84

Well it has been a while since Ive done the bearing, but what I can recall is that I definately removed the caliper harness. Also, the forcing that I did was probably done with some sort of clamp device. Which in turn did not work well if I still had a hard time manuevering the caliper back onto the rotor. I didn't change the pads or rotors at that time but I believe I tried to set the piston back without success. As of right now, the car has a new set of rear brakes and rotors on. The parking brake lights on the dash and on the lever blink simultaneously, the abs light, and (brake light) are also on. Brakes work fine parking brake engages but seems weak. I'm running out of ideas. Just tried resetting by disconnecting the battery. Now the traction control light is on lol. Im Running out of ideas.

mishar

Running out of ideas is not always bad thing. Depends on ideas.

Forcing it with clamp you probably damaged the spindle, or some other part of that mechanism that engages perking brake. Weak parking brake is probably just one side working.

What does VCDS scan tell about parking brake?

Fashizzkes84

The vcds tells me that the voltage is bad for both sides of the motor. And to change the pads

Fashizzkes84

02432,02433

sean59

I'm getting an implausible signal and Audi diagnosed it as the rear passenger speed sensor wiring fault. Yes I did replace the wheel bearing and all of this went wrong after that. When I did the replacement of the rear pads procedure fro opening the parking brakes they retract like they should and the compress 3 times I think, so all seems to be OK with the parking brakes and both sides go up to around 14 amps when closing so I'm pretty sure they are working ok. Is it possible I damaged wiring to the speed sensor? I checked continuity for 6 inches or so from the plug and it appears to be OK and I also put a new speed sensor on and got the same result. How do I check this further? I pulled the connector off the ABS module and found brown wires with the insulation flaking off and I temporary repaired them with electrical tape and I may not have gone back far enough. Likely culprit and keep going further back, or am I missing something obvious as this would not have been caused by a wheel bearing job.
Any assistance would be very much appreciated.

Dan McBoost

When I had the ABS/Parking brake/Light leveling errors at the same time, it was a failing ABS bosch unit I had rebuilt. There has been records on here of wire insulation coming off after heat cycles over the years.