ABS going nuts!!

**Boosted-S4** · 01-03-2009 04:14 PM

Yes,yes...another problem has come up.This time is the ABS. A few months ago my ABS control module gave up on me.After finding out from the dealer that a new ABS control module for my S was 1800 + tax i decided to get myself a rebuilt unit.The problem?????
When driving around and slowing down ..not a problem...but when im about to reach a complete stop (around 10KM/H) the ABS kicks in...ive tried steping on the brake at a fairly high speed, but nothing. Only when im about to come to a stop is when the ABS comes on!!
what the hell is going on??? Vag shows no codes>

help needed guys!!!

**Dallas09** · 01-03-2009 04:22 PM

If you do a bunch of multiple slow speeds in a stop in a row it should eventually throw a code since it will be the same wheel sensor doing causing it to happen in a row. The other option is to go to measuring blocks, this will show speeds for each wheel individually, look for the one that is jumpin around. Measuring blocks on ABS only works at low speeds I believe (mine disconnects when you get going faster for some reason).

If it did this immedietly started doing this after your rebuilt unit, i might consider returning it, that would be a pretty big coincidence.

**Boosted-S4** · 01-04-2009 02:16 PM

Before I installed the rebuilt unit my ABS module was so screwed up that i couldnt even get inside with VAG.After the instalation ,while having the VAG pluged in we took it for a spin and everything was fine,no codes whatsoever,but when we came to a stop the abs still kicked in!!

I have no idea what is going on and my mechanic said it was the first time he ever came across such problem.

Does anyone have any idea what the hell is going on?? The ABS is working but its damn annoying everytime ur coming to a stop to have that ABS come on and have that feel on the pedal!!

Help needed please!!!

**lowered97a4** · 01-04-2009 02:59 PM

sounds like my problem i had it was the tone ring on the cv joint where the speed sensor picks up they crack throws off the sensor, most likely one of the rear joint rings is cracked, if not that then a speed sensor might be dirty

**Boosted-S4** · 01-04-2009 03:40 PM

how much for the part + labour?
am i looking to spend hundreds to get it fixed??
by the way..thanx for the info..greatlly appreciated.. + rep

**MacDaddy** · 01-04-2009 04:50 PM

Originally Posted by lowered97a4

sounds like my problem i had it was the tone ring on the cv joint where the speed sensor picks up they crack throws off the sensor, most likely one of the rear joint rings is cracked, if not that then a speed sensor might be dirty

that's what I'm thinking, I've read about 3 different posts on here where that was the cause for the above mentioned symptoms.

**devildog6** · 01-04-2009 05:16 PM

Originally Posted by lowered97a4

sounds like my problem i had it was the tone ring on the cv joint where the speed sensor picks up they crack throws off the sensor, most likely one of the rear joint rings is cracked, if not that then a speed sensor might be dirty

my wife hit a piece of wood in the road do you think that could crack the tone ring, if so how can i DIY fix?

**Aggv** · 01-04-2009 09:18 PM

I have this exact same problem. I think the jerk off who installed my brakes messed something up.

**Dallas09** · 01-04-2009 09:23 PM

Yeah its a common problem.. Assuming the module they sent you is alright (which is most likely since there are no other issues and this only happens at a low speed, it doesnt occur all the time)... Its a dirty or damaged wheel speed sensor, or the CV ring. If you use a VAG and do what I said above, you can figure out which one is causing the problem. Sensors are less than a hundred and CV joints are right around 100, it may also be possible for the ring only to be replaced. It could just as easily be that the sensor is dirty and needs to be cleaned, this is also a very common problem.