Rear wheel speed sensor problem!!

[clanofwolves]

I have the dash warning lights 'break' and 'ABS' Illuminated on my dash for about a week. When I shorted the jumpers on the diagnostic hook-up, I was given the flashing codes: 33 and 38 which both indicate a problem with the right rear wheel speed sensor. I checked all of the electrical wire harness that lead to the right rear wheel speed sensor and they're fine.

Does anyone know what might be the problem with the sensor? How can I diagnose it? And how do you replace it? (none of this is covered in my Haynes manual)

Thanks in advance for ANY help in this unusual problem!!

Dave

[clanofwolves]

I have read on this forum that if a sensor is broken and free from the hub, the rear bearing needs to be replaced (the sensor is part of the assembly). But, if it is all intact, then what? replace the bearing assembly?

[Potter]

That poster was wrong when he said it had to be replaced. I was able to salvage mine and posted details in that thread.

If you haven't fixed it yet, dry unplugging the cable that leads to the rear right sensor and cleaning the contacts with an electrical contact spray. Mine were visibly in need.

Hope you find an easy fix.

[clanofwolves]

I have disconnected and reconnected the connectors for the rear passenger ABS lines and they looked OK, but I did not clean them with a electrical contact spray. I will give that a shot too.

Thanks!! I'll let you know if it worked...

[needs_help]

I also want to clean a rear wheel ABS sensor in my car and have some questions. Will I need to jack up the car? Is a regular jack strong enough? Do I need to use 2 jacks? Also, do you have a link to the electrical contact cleaner that you bought?

[Potter]

No need to jack the car because everything is within easy (well, sorta easy) reach.

Looking at the rear wheel assembly from under the car, near the lower shock mount, there's a wire that plugs into the ABS/TP sensor. It has a rubber boot on it, which might fail to do its job and let water in. Carefully unplug it and look for clean contacts on both ends - on the wire end and on the sensor end. I reached up with a camera and took some pics of the connector on the sensor end because that's a lot easier to look at. The wire end was easy. You might also check that the assembly (I posted a pic in my thread on the subject) is securely glued in place. Mine wasn't, and I fixed that by brushing JBWeld with a new plumbing soldering brush. That brush was perfect for smearing the stuff where it was needed. We've gone about 3500 miles with the fixed sensor, so I assume it's OK. Originally, it had fallen off the axle and was dangling on the car held to the car only by the wires.

The spray I used was just common electrical contact cleaner. I got mine at an online electronics store, but Radio Shack and places like that likely have it too. I think I once saw it at Walmart, in the auto section amongst the spray chemicals. We also use that stuff, it's like pixie dust, on our trailer wiring connector -- it looks fine but simply fails to work sometimes and that spray fixes it every time.

One thing you might want to look for On the schematic it appears the wire leading to the sensor has another connection somewhere, maybe under the car and it looks like the wires feed into a larger cable. You might want to follow the wire and see where it goes. But on that one I'm not sure as I never found it, and it might be a wild chase.

Good luck!