View Full Version : Brake Light & Pad Message Still On After Changing Pads...Need Help
dadman
07-26-2019, 10:07 AM
This seems to be a somewhat known issue but before I take it to my dealer and get a shaft that I don't need......has anyone found a fix or a reason for this to keep happening? The Audi tech said that in 10% of cases it's the harness that the sensor plugs into that's at fault. Pads are OEM w/ new sensor wires, the harness that he's talking about is a 4G0972251E and it's a "repair harness" which probably means that it needs wires to be cut and spliced, not really what I want to do unless absoultely necessary.
RAF_S7
07-26-2019, 04:33 PM
Do you still have the old sensors?
The actual sensor itself is just a wire loop, that gets worn away as the pads wear down. You could simply make a loop back/short in the old cable, plug it into the harness in place of the installed sensors (1 at the front, one at the rear, both passenger side in US) and see if that fixes the problem. At least this would eliminate the need for the “repair cable” issue.
I believe (not 100% sure) that you have to reset the warning light using the VCDS/OBD11 type tool. [wrench]
dadman
07-26-2019, 06:50 PM
Do you still have the old sensors?
The actual sensor itself is just a wire loop, that gets worn away as the pads wear down. You could simply make a loop back/short in the old cable, plug it into the harness in place of the installed sensors (1 at the front, one at the rear, both passenger side in US) and see if that fixes the problem. At least this would eliminate the need for the “repair cable” issue.
I believe (not 100% sure) that you have to reset the warning light using the VCDS/OBD11 type tool. [wrench]
Don't think that there is a reset. Right now I would like to find out what's wrong before I go that route.
bahula03
07-26-2019, 11:52 PM
There's a reason that VCDS and the dealer computers have a specific function for replacing the rear brake pads? It's certainly possible that the harness is broken or one of the new wear sensors is defective, but seems more likely the computer is just grumpy. The last bit of the first post is probably the most helpful to you; cycle the parking brake a few times so it can relearn where engagement happens and then clear any stored codes. And like RAF_S7 said, you can easily use the old wear sensors to help isolate the issue.
https://www.audiworld.com/forums/a6-c7-platform-discussion-194/diy-brake-pads-rotors-3-0t-2904638/
http://wiki.ross-tech.com/wiki/index.php/Audi_A6_(4G/4H)_Parking_Brake
dadman
07-27-2019, 07:06 AM
Do you still have the old sensors?
The actual sensor itself is just a wire loop, that gets worn away as the pads wear down. You could simply make a loop back/short in the old cable, plug it into the harness in place of the installed sensors (1 at the front, one at the rear, both passenger side in US) and see if that fixes the problem. At least this would eliminate the need for the “repair cable” issue.
I believe (not 100% sure) that you have to reset the warning light using the VCDS/OBD11 type tool. [wrench]
Don't think that there is a reset. Right now I would like to find out what's wrong before I go that route, good idea about jumping the wire out
dadman
07-27-2019, 07:08 AM
There's a reason that VCDS and the dealer computers have a specific function for replacing the rear brake pads? It's certainly possible that the harness is broken or one of the new wear sensors is defective, but seems more likely the computer is just grumpy. The last bit of the first post is probably the most helpful to you; cycle the parking brake a few times so it can relearn where engagement happens and then clear any stored codes. And like RAF_S7 said, you can easily use the old wear sensors to help isolate the issue.
https://www.audiworld.com/forums/a6-c7-platform-discussion-194/diy-brake-pads-rotors-3-0t-2904638/
http://wiki.ross-tech.com/wiki/index.php/Audi_A6_(4G/4H)_Parking_Brake
My fault...it's the front that I worked on, it still could be a coincidence and the light is coming on due to a problem in the rear. Thanks
FWIW I just replaced the rear pads utilizing VCDS and battery charger as required.
As pointed out...cycling the parking brake is necessary.
The car actually throws quite a few codes as bahula points out and not just for the brakes but also the ACC and ABS which needs to be cleared.
I think 4 modules had faults after finishing also the ones for ACC would not clear using the gateway install list DTC clearing. I had to clear them from each module individually.
3g_bishi
07-27-2019, 10:23 PM
Do you have vcds you can do a code scan to find out what’s wrong? Also resetting is the proper thing to do if there is a reset, confused by what you mess that you don’t want to go that route? If there is an issue the reset won’t work. If no issues are found then a reset would solve your problem.
Sent from my iPhone using Audizine (http://r.tapatalk.com/byo?rid=87676)
doublezero30
07-28-2019, 06:16 PM
when i worked for audi back in MA id see that harness the sensor plugs into be bad fairly commonly. that would be my guess
PSUGOLD
07-28-2019, 06:42 PM
My S4 did the same thing, my brake pad wear sensor had a loose wire and it was causing the error. $7 later, all fixed.
dadman
08-04-2019, 03:14 PM
when i worked for audi back in MA id see that harness the sensor plugs into be bad fairly commonly. that would be my guess
The Tech told me about 10% of the time that's what it is. Is there a way to tell if it's the front or rear that's doing it? Or does a VCDS pick it up, I have one?
doublezero30
08-05-2019, 05:34 PM
The Tech told me about 10% of the time that's what it is. Is there a way to tell if it's the front or rear that's doing it? Or does a VCDS pick it up, I have one?
i wasnt a tech but id think vcds would tell you front or rear.