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Anyone successfully "repair" the ABS front wheel speed sensor?

25K views 17 replies 8 participants last post by  dubluvpassat01  
#1 ·
I did my CV joint tear down and rebuild and I must have done something to the speed sensor in the hub as the "ABS" light comes on usually when I am driving. Anyone successfully fix this or is it ruined and I need a new one? Can I just mineral spirit it up? Also I have seen posts online (ebay) for the part listed as

Audi A3 A4 A6, TT, Quattro 1999-2005
Volkwagen Golf, Jetta, Passat, Beetle 1999-2005


Anyone think this will fit my 99 AEB? Drew parts and others are in the 120-168 dollar range for this part.

Thanks for any informed comments.
 
#4 ·
I have the same fix to do.

Have you tried cleaning the face of the sensor - lots of reports of rust/dirt sticking to the face. I haven't had a spare moment to give it a go myself.

ÂŁ100 ish over here which is around $200
 
#5 ·
I've had luck cleaning the sensor and reinstalling. The sensor has to be inserted *all* the way to work correctly. Cleaning seems to let it seat that extra tenth of a millimeter.
 
#6 ·
I've had luck pulling ABS sensors and cleaning them in the past.

The magnet(s) on the sensors pick up any metallic particles from the brake pads and get covered up with brake dust.

The sensors are usually attached to the hub by either a 5mm or 6mm allen head bolt. After removing the bolt, the sensor may be difficult to remove due to all the build-up. After it's out, clean both the sensor and the hole it came out of with a toothbrush and mineral spirits then reinstall.
 
#11 ·
I've done this several times on my Audi A4. Whenever I have changed suspensions (4 times) I have had one or both front sensors have problems. They simply pull out with a little effort and twisting. I also used PB blaster to help them as they are very tight. Most of the problem seems to be rust and debris from the rotors getting dislodged from removing tight bolts on the suspension. I used brake cleaner and liberally sprayed into the holes while turning the rotors and also some air pressure to clean out any debris. I used emery cloth for the actual sensors and cleaned them with brake cleaner before reinstalling. My Audi has 118,000 miles on it and I'm still on the original sensors.
 
#12 ·
I pulled it out last night and there was some garbage on the tip but I cleaned them all off and used solvent and cleaned it off. Pushed them back on and the same error popped up. NOt ery hard to get to but I dont want to keep jacking the car up over and over to keep trying this is a new sensor will solve it. Who knows.
 
#14 ·
Turn your wheels all the way to the right and your can remove it without jacking the car...although you will get dirty. Or left if its on that side.

I replaced my sensor, but it was obviously smashed at the end (thanks mechanic). Replacement was easy as it seems.
 
#15 ·
I pulled it all apart again and starting taking pictures to post on here on how to repair and clean it up but my cleaning must have failed as the light ABS light came right backup as soon as I cranked the engine up. I didn;t use a toothbrush inside the sleeve but I could see down into the hub abd turned the cv joint and used a finger and a rag to clean most of it clean. I am curious what antoddio mentions above about it was obviously smashed. Mine does have a flat spot on the end but I though that was by design. Maybe mine got smooshed?
 
#17 ·
I have cleaned mine several times with success. Dirt and debris gets on the rotating ring and I use brake cleaner in a spray can and spray into the opening after removing the sensor while rotating the hub. I spray a lot to loosen any debris up and then after it dries, I spray compressed air into the sensor hole while rotating again. The only time I have to clean these is after I change suspension components or steering components. The last time was last summer when I changed my control arms and put in new coilovers. I have found that most (but not all) of the problem is not the sensor but inside the mounting hole and rotating ring. Also a light tap with a soft hammer may help seat the sensor after everything is cleaned up.
 
#18 · (Edited)
DANTESHORS: What year is your Passat? I have an xtra ABS sensor from a steering knuckle I got @ a boneyard. Instead of two plugs that go in the fender liner of the wheel well (+ -) it has one large black plug. I think its from a 99. I don't know if it works. If your ABS sensor is the same (I'll post a pic this afternoon) I'll mail it 2 you for free. Just give me a PM later.