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Glenns Audi
01-29-2011, 02:20 PM
So I have the dreaded ABS light with the blinking brake light. I have read multiple threads about other members diagnostics (unfortunately I do not have Vag-Com) and I have done the other checks to try to figure it out. Most likely it is the ABS module but I still just want to clean the rear wheel sensor that people are talking about. I've seen and read the links to the A8 where it is suposedly the same as ours.

anyone tell me exactly tell me (or show me with a pic) where this speed sensor is in the rear? I swear I have looked at it for 10 minutes and cannot locate it as easy as the front ones. By the way I have a 99.5 A4 B5 QMT.

Thanks in advance guys.
- Glenn

Dallas09
01-29-2011, 10:19 PM
If it were an ABS sensor you SHOULD only get the ABS light and no flashing brake light. Generally if you have the combo, you either have a bad module, no power to the ABS module, or no communication with the instrument cluster. If you have a bad sensor, you get a solid ABS light ONLY. I have heard one person claim they had the combo with a bad sensor on the forum, but almost everyone else says it goes the former. Anywho, if you want to take a look, http://www.google.com/imgres?imgurl=http://www.audipages.com/Tech_Articles/susp_whls_brake_steer/absrepair6.JPG&imgrefurl=http://www.audipages.com/Tech_Articles/susp_whls_brake_steer/abstroubleshooting.html&usg=__ZYDl9F6Et9C2jnguP8W1HE6hx7U=&h=480&w=640&sz=68&hl=en&start=0&zoom=1&tbnid=WAlO7waaJRE0bM:&tbnh=138&tbnw=183&ei=rAJFTYCvF4GdlgehqMH4Dw&prev=/images%3Fq%3Daudi%2Babs%2Bsensor%26um%3D1%26hl%3De n%26sa%3DN%26biw%3D1366%26bih%3D681%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=306&vpy=183&dur=363&hovh=194&hovw=259&tx=130&ty=107&oei=rAJFTYCvF4GdlgehqMH4Dw&esq=1&page=1&ndsp=21&ved=1t:429,r:1,s:0 , it looks the same except the rears have a little bolt holding them on as well I believe.

Glenns Audi
01-29-2011, 10:34 PM
If it were an ABS sensor you SHOULD only get the ABS light and no flashing brake light. Generally if you have the combo, you either have a bad module, no power to the ABS module, or no communication with the instrument cluster. If you have a bad sensor, you get a solid ABS light ONLY. I have heard one person claim they had the combo with a bad sensor on the forum, but almost everyone else says it goes the former. Anywho, if you want to take a look, http://www.google.com/imgres?imgurl=http://www.audipages.com/Tech_Articles/susp_whls_brake_steer/absrepair6.JPG&imgrefurl=http://www.audipages.com/Tech_Articles/susp_whls_brake_steer/abstroubleshooting.html&usg=__ZYDl9F6Et9C2jnguP8W1HE6hx7U=&h=480&w=640&sz=68&hl=en&start=0&zoom=1&tbnid=WAlO7waaJRE0bM:&tbnh=138&tbnw=183&ei=rAJFTYCvF4GdlgehqMH4Dw&prev=/images%3Fq%3Daudi%2Babs%2Bsensor%26um%3D1%26hl%3De n%26sa%3DN%26biw%3D1366%26bih%3D681%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=306&vpy=183&dur=363&hovh=194&hovw=259&tx=130&ty=107&oei=rAJFTYCvF4GdlgehqMH4Dw&esq=1&page=1&ndsp=21&ved=1t:429,r:1,s:0 , it looks the same except the rears have a little bolt holding them on as well I believe.

Thats basically the same thread I read. I did see something where a bolt was holding something, that must be it. Would you happen to know what bolt is holding it down? Thanks!

Dallas09
01-29-2011, 11:27 PM
Youll know when you see it, without a doubht, its like within a centimeter of the abs speed sensor and the wire. If you have done much research, youll know that they can be impossible to remove without damaging them however. They end up seizing into the wheel carrier, and you really cant remove them without either damaging them, or by removing the wheel carrier to punch them out from the other side.

Glenns Audi
01-30-2011, 08:59 AM
You're right. I'll go the ABS module route and hope that fixes the issue. Thank you sir!