Testing ABS wheel Sensor ABS Light on
 

Does anyone know where to start checking the harness to my ABS wheel sensor. I changed my unit bearing a month ago Started with left side one week .had no problems The next week I changed the right side from then on my abs light stays on A/E says c1145Speed sensor RF input circuit failure. I have tried using my other sensors from the old unit bearings but it doesnt help

You can disconnect the sensor wire and do a continuity check at the ABS module. That will at least tell you the wires are good. If it worked before I would think it isn't damaged.

http://i626.photobucket.com/albums/t.../ABSWiring.png

Ok I will try that is the ABS Module under the dash? It worked up until I unpluged the the sensor to change the unt bearing I dont Know if I broke a wire when I unpuged it or if the wheel sensor in the new unit bearing was no good

I would start by looking at the connector pins at the sensor, you may have pushed one back in the truck side connector.

I checked that I even removed the pins from the connector and pluged them in directly to the sensor

Did you ohm out each sensor to see how they compare?

No not yet I have to get a meter tomorrow

There may also be a chance that the new unit bearing is somehow defective and the trigger is not correct. You may want to pull the sensor out and try to look in the hole. If you have the old one still you can compare what you see.

Check the wires under the wheel wells carefully. I had a "bad" place on a wire that was in a hard to see place. Actually, something had nicked it and it was about in 2 pieces. Spliced the wire and was back in business. I hope yours is something simple like that. Good luck and keep us posted.

Ok thanxs Guys I figured it out The sensor in the new unit bearing was no good. I used my new meter and OHM the sensor and got nothing so I used one of my old sensor and it all works now. Now I guess on to beating out Ball joints.

Good deal! Glad you got it figured out.

In Post #1 you indicated that you had already tried the sensors from your old hubs, and that it didn't give you different results.

What happened this time to cause one of them to work?

Pop

When i tried the old sensors they where in the old unit bearings I pluged it into the truck then spun the bearings as fast as I could which didnt reset the abs light. It wasnt untill i checked the sensor with a multi meter on the lowest AC voltage setting there was a rise and fall in voltage generated by the sensor when the bearing is spun rapidly on the old one and not the new one and when I checked for ressitance the new on showed 0 and the old sensor gave me a reading. so I removed the sensor from the new unit bearing and replaced it with the used one put it all back toghter and went for a drive the abs light stayed on untill I got to a certain speed then it went out. I guess when I was spining the bearing by hand it wasnt fast enough to reset the abs light.