2004 Grand Prix - ABS/Traction Control Problem won't stop

I have been having this issue in driver front side since Feb. 2010. I’ve had the ABS sensor and bearing in this wheel replaced twice; also all 4 wheels’ brake pads, rotors and caliphers replaced; parking brake replaced. My mechanic (not dealer) is master mechanic and has 3 other mechanics in a forum working on this - no luck yet. Also there was an issue with wiring for the AC compressor which run beside/near the sensor - it was worn and mechanic thought it was arcing over and making sensor go off. I get lights daily, plus the grinding/grabbing of the brakes. Does anyone think this might be computer malfunction, i.e. sending false signal to ABS system? My mechanic is going to try to find used one to see if it helps. Any suggestions by anyone would be so appreciated. About to drive it off a cliff and I live in North TX - no cliffs nearby! thanks!

Grinding and grabbing brakes would not have anything to do with the ABS system. If you have a team of mechanics working on this car and they can’t fix your problem I doubt any online forum is going to figure it out for you.

It seems that you have reached the end of your “master mechanics” abilities. If I were you I would find another set of eyes to peruse the situation.

I guess I should have been a little more specific - the “grinding and grabbing” is really the ABS pump kicking in when it shouldn’t.

Could be the rubber brake line is colapsing internally and keeping pressure on the caliper when the brakes are released. I would replace both.

I had the exact same issue with my 2004 Pontiac Grand Prix, it was diagnosed with a bad wheel bearing ( where the sensor was BTW) and no more issues, mine has 160,000 miles on it and was a $200 fix

How old are your tires? And are there any differences side to side?

It is possible to end up with tires of different diameter - even if they’re the same size tire - that trigger ABS activity.

I don’t think this is very common, but I have experienced it myself (and on a GM vehicle). In my case it was all very low speed ABS activation.

Has Anybody Consulted The GM Technical Service Bulletin Pertaining To The ABS Light And A Revised ABS Wheel Speed Sensor Jumper Wiring Harness ? It Includes The 2001 - 2004 Grand Prix Models.

The harness part numbers (R & L available) are listed and instructions for splicing.

Don’t know if this will fix your problem, but you do need a technician that can access and use the bulletin and properly diagnose and resolve this problem.


Did The Mechanic “Repair” The Worn Wires ?

For certain problems, a GM dealer might be the best place to go. This could be one of those.