ABS problem?
01-27-2012, 03:48 PM
#11
Audiworld Junior Member
Thread Starter
Join Date: Jul 2004
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
This is a tone ring on a CV joint.
https://www.audiworld.com/forums/sho....php?t=2054269
Generally if the tone rings aren't physically cracked or worn (they should have NO wear on them..if they do something like the sensor got pushed in or a rock damaged it) they're ok. I don't think the rings can be replaced w/o replacing the out CV joint but look around...I recall reading about some guy who made a bunch of them from billet or found Taurus rings that could be pressed on.
Clearly anyone who rebuilds CV joints has access to tone rings.
https://www.audiworld.com/forums/sho....php?t=2054269
Generally if the tone rings aren't physically cracked or worn (they should have NO wear on them..if they do something like the sensor got pushed in or a rock damaged it) they're ok. I don't think the rings can be replaced w/o replacing the out CV joint but look around...I recall reading about some guy who made a bunch of them from billet or found Taurus rings that could be pressed on.
Clearly anyone who rebuilds CV joints has access to tone rings.
Thanks for the insight!
01-28-2012, 02:06 PM
#12
AudiWorld Super User
so it is the actual "encoder" ring that the sensor reads? I was going to look again through the sensor hole to see if I can see any damage. Is it correct that there really isn't an adjusment for my year and model? The sensors bolt right on so I can't see how they would be adjusted.
Thanks for the insight!
Thanks for the insight!
01-29-2012, 08:22 PM
#13
AudiWorld Member
Join Date: Dec 2007
Location: Anacortes, WA
Posts: 102
Likes: 0
Received 0 Likes
on
0 Posts
I had a similar, intermittent problem with my 2002 S6. I would get the same Yaw sensor codes. The brake noises you're getting could be The ESP being activated.
I replaced the Yaw sensor, but it didn't fix the problem. Eventually,without any confirming fault code, I replaced the ABS module, which did solve it. I bought a brand new Audi part, but Module Masters, and others, can repair them.
The problem seems to be with soldered, fine wire circuit board connections inside the ABS control module.
I replaced the Yaw sensor, but it didn't fix the problem. Eventually,without any confirming fault code, I replaced the ABS module, which did solve it. I bought a brand new Audi part, but Module Masters, and others, can repair them.
The problem seems to be with soldered, fine wire circuit board connections inside the ABS control module.
01-30-2012, 07:23 AM
#14
Audiworld Junior Member
Thread Starter
Join Date: Jul 2004
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
I had a similar, intermittent problem with my 2002 S6. I would get the same Yaw sensor codes. The brake noises you're getting could be The ESP being activated.
I replaced the Yaw sensor, but it didn't fix the problem. Eventually,without any confirming fault code, I replaced the ABS module, which did solve it. I bought a brand new Audi part, but Module Masters, and others, can repair them.
The problem seems to be with soldered, fine wire circuit board connections inside the ABS control module.
I replaced the Yaw sensor, but it didn't fix the problem. Eventually,without any confirming fault code, I replaced the ABS module, which did solve it. I bought a brand new Audi part, but Module Masters, and others, can repair them.
The problem seems to be with soldered, fine wire circuit board connections inside the ABS control module.
Thanks!
01-30-2012, 08:27 AM
#15
AudiWorld Super User
I had to replace the electronic module in my 2K4.2A6 because the ABS and BRAKE LED's were lit on the instrument cluster. Various shops will repair yours and you can drive without it..you just don't have ABS (or ESP but my 2K4.2A6 didn't have ESP and I don't miss it) for a couple weeks.
On my 02S6, I had to replace the yaw sensor because the ESP LED kept coming on...it would reset if I shut off and turned on the ignition but eventually came on all the time. The 02S6 has not had the ABS electronic module replaced.
Sounds to me more like your yaw sensor is kaput.
On my 02S6, I had to replace the yaw sensor because the ESP LED kept coming on...it would reset if I shut off and turned on the ignition but eventually came on all the time. The 02S6 has not had the ABS electronic module replaced.
Sounds to me more like your yaw sensor is kaput.
01-30-2012, 09:14 AM
#16
Audiworld Junior Member
Thread Starter
Join Date: Jul 2004
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
I had to replace the electronic module in my 2K4.2A6 because the ABS and BRAKE LED's were lit on the instrument cluster. Various shops will repair yours and you can drive without it..you just don't have ABS (or ESP but my 2K4.2A6 didn't have ESP and I don't miss it) for a couple weeks.
On my 02S6, I had to replace the yaw sensor because the ESP LED kept coming on...it would reset if I shut off and turned on the ignition but eventually came on all the time. The 02S6 has not had the ABS electronic module replaced.
Sounds to me more like your yaw sensor is kaput.
On my 02S6, I had to replace the yaw sensor because the ESP LED kept coming on...it would reset if I shut off and turned on the ignition but eventually came on all the time. The 02S6 has not had the ABS electronic module replaced.
Sounds to me more like your yaw sensor is kaput.
Thanks.
01-30-2012, 09:26 AM
#17
AudiWorld Super User
I had the yaw sensor replaced under warranty. IIRC the bag-com may have had to recenter the steering angle or some such. IIRC driving in a circle recalibrates the compass...unaware of this for the yaw sensor.
There IS an ESP road test that is supposed to be carried out if you replace the yaw sensor or any other part of the ESP system. It involves right and left turns and a turning rate of 10 degrees per second but you're not supposed to do anything that activates the ESP, ABS, etc. systems. It's not a calibration, it simply checks the plausibility of the signals from the various sensors. If the test fails it hasn't been performed properly or there is a malfunction in the system and you're back to square one...a bad new yaw sensor or something else.
There IS an ESP road test that is supposed to be carried out if you replace the yaw sensor or any other part of the ESP system. It involves right and left turns and a turning rate of 10 degrees per second but you're not supposed to do anything that activates the ESP, ABS, etc. systems. It's not a calibration, it simply checks the plausibility of the signals from the various sensors. If the test fails it hasn't been performed properly or there is a malfunction in the system and you're back to square one...a bad new yaw sensor or something else.
Last edited by SloopJohnB@mac.com; 01-30-2012 at 09:42 AM.
01-30-2012, 10:03 AM
#18
This problem may be much more involved, and I may be going in the wrong direction, but I can tell you this. I had a 2.7T A6 that randomly had the esp and/or ABS lights pop on. It popped on almost anytime you drove it, but it was super random - it could be on the highway doing 70, on a back road, on a straight away, on a turn, on a turn braking, braking straight, not braking, you name it. Everytime I thought I figured something out, something else would set it off.
I scanned with the vag and at one point, the yaw sensor code was there. I knew I wasn't going to spend so much on a sensor without knowing for sure, so I kept digging and finally decided to replace the brake switch for the hell of it.
This did NOT fix the light. I then scanned with the vag-com while hitting the brake pedal.
What I found is that the first fraction of a centimeter of pedal movement activates a "test" switch for the brake lights. The rest of the movement activated the light switch. The switch, which was a screw in type with threads on it, was not adjusted correctly and the "test" switch was always active, even with the foot off the pedal. The car always thought the brakes were on, even though the lights were off.
I adjusted the new switch, and the lights were gone forever.
I scanned with the vag and at one point, the yaw sensor code was there. I knew I wasn't going to spend so much on a sensor without knowing for sure, so I kept digging and finally decided to replace the brake switch for the hell of it.
This did NOT fix the light. I then scanned with the vag-com while hitting the brake pedal.
What I found is that the first fraction of a centimeter of pedal movement activates a "test" switch for the brake lights. The rest of the movement activated the light switch. The switch, which was a screw in type with threads on it, was not adjusted correctly and the "test" switch was always active, even with the foot off the pedal. The car always thought the brakes were on, even though the lights were off.
I adjusted the new switch, and the lights were gone forever.
01-30-2012, 11:27 AM
#19
Audiworld Junior Member
Thread Starter
Join Date: Jul 2004
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
This problem may be much more involved, and I may be going in the wrong direction, but I can tell you this. I had a 2.7T A6 that randomly had the esp and/or ABS lights pop on. It popped on almost anytime you drove it, but it was super random - it could be on the highway doing 70, on a back road, on a straight away, on a turn, on a turn braking, braking straight, not braking, you name it. Everytime I thought I figured something out, something else would set it off.
I scanned with the vag and at one point, the yaw sensor code was there. I knew I wasn't going to spend so much on a sensor without knowing for sure, so I kept digging and finally decided to replace the brake switch for the hell of it.
This did NOT fix the light. I then scanned with the vag-com while hitting the brake pedal.
What I found is that the first fraction of a centimeter of pedal movement activates a "test" switch for the brake lights. The rest of the movement activated the light switch. The switch, which was a screw in type with threads on it, was not adjusted correctly and the "test" switch was always active, even with the foot off the pedal. The car always thought the brakes were on, even though the lights were off.
I adjusted the new switch, and the lights were gone forever.
I scanned with the vag and at one point, the yaw sensor code was there. I knew I wasn't going to spend so much on a sensor without knowing for sure, so I kept digging and finally decided to replace the brake switch for the hell of it.
This did NOT fix the light. I then scanned with the vag-com while hitting the brake pedal.
What I found is that the first fraction of a centimeter of pedal movement activates a "test" switch for the brake lights. The rest of the movement activated the light switch. The switch, which was a screw in type with threads on it, was not adjusted correctly and the "test" switch was always active, even with the foot off the pedal. The car always thought the brakes were on, even though the lights were off.
I adjusted the new switch, and the lights were gone forever.
01-30-2012, 04:42 PM
#20
After thinking about what happened to me more, the switch that was problematic was a screw in type. I believe they did away with this in 2002, and you have a 2003, so there really isn't adjustment to be made I don't think - you just put it in and turn 90 degrees.
If you have a vag-com, hook it up and check out your brake module. This is what I did and that's when I noticed that the test switch was always enabled, but the brake switch went on and off just like normal. I was lucky enough to have a second car that worked and realized the test switch should go off and on just like the brake switch.
Maybe playing around will give you some more insight. That yaw sensor is crazy expensive to at least not have a good diagnosis for.
Also, take it out to a parking lot and watch the reading on each of your wheel speed sensors, make sure those are all reading accurately. If one is off, that may be a bad sensor, or I believe may actually back up what sloop is saying more. Not sure though...
If you have a vag-com, hook it up and check out your brake module. This is what I did and that's when I noticed that the test switch was always enabled, but the brake switch went on and off just like normal. I was lucky enough to have a second car that worked and realized the test switch should go off and on just like the brake switch.
Maybe playing around will give you some more insight. That yaw sensor is crazy expensive to at least not have a good diagnosis for.
Also, take it out to a parking lot and watch the reading on each of your wheel speed sensors, make sure those are all reading accurately. If one is off, that may be a bad sensor, or I believe may actually back up what sloop is saying more. Not sure though...