Has anyone ever replaced the magnetic strip that goes around the CV joint for the ABS brake? I dented one of the tabs and I think it is throwing off my ABS. I am not sure if it is that or the sensor.

The ABS comes on WAY to early, but I am not getting a warning light. This happened when I changed the drivers side rear wheel bearing.

Any suggestions?

Chip

 

Define "Way too early". Are you sure that all your tire pressures are the same, and your brakes are in good condition (no air bubbles, good pads, etc.). Are you experiencing this issue after the brakes are completely warmed up on a smooth, dry road?

 

The brakes were working fine before I replaced the wheel bearing. When I put it all back together, I wiped off the upper ball joint grease with a rag that had some shavings on it (I didn't see them). When Itest drove the car the first time, the ABS light was on and the ABS was not working.

I came back and checked the sensor and saw the shavings. I wiped it off with a clean rag and put it back together. The ABS light stayed off, but the ABS comes on when doing a normal stop, no wheel slip.

I did notice that one of the "tabs" on teh hub ring was dented. I didn't know if that changed the magnetic frequency when the wheel was turning or whether the shavings that were on teh rag some how changed the magnetic polarity of something.

 

Also, I tested it on wet and dry roads.....warm and cool.

 

Its the toothed pattern of the sensor wheel as it passes under the magnetic ABS sensor thats important. If one of the teeth of the sensor wheel has been rounded off then that could certainly cause the problem you have. As a side note, one of my sensor wheels got a bit messed up when i had a wheel bearing go out on me. The bearing caused enough play that the ABS pickup actually contacted the sensor wheel and caused some of the shavings you speak of. My suggestion would be to gain access to the sensor wheel and with a small file make sure all the teeth have straight edges.

 

Are you saying shave it off level again? I know that tehy have to no more then 1 mm away from the sensor, so I am not sure if that will help.

The shavings came from the rag. It was next to my drill press and I did not see the little shavings.

 

Check the amount of space between the sensor and the ribs on all of your hubs, to make sure that they are all about the same. Maybe the sensor bracket was bent during the bearing change, and there is too large of a gap (I'm guessing).

 

Is there a way to change just the ribs on the CV shaft? Does it come off?

If the bracket for the sensor is bent, that means the whole hub assembly is bent. I don't think it is that, but anything is possible.

 

Do as Gurnby suggests... Check to make sure the pickup is seated properly in its socket. The shavings you and I are talking about are different. My shavings came from the ribbed sensor wheel when it managed to make contact with the magnetic pick up while the car was in motion. The point I was trying to make is that you want the teeth on the wheel to be square and not rounded. There is no easy way to replace the ribbed wheel. Replacement will require you to at least remove the axle nut for that wheel.

 

I can remove the axle nut without a problem, I just did it.

I am just wondering if I have to replace the whole CV Joint or whether the ring will come off.

I am going to check again to see if the sensor is seated correctly. But, if it was to far off, wouldn't the ABS light come on and disengage the ABS? That is why I was thinking it was the ring.