I have an 05 GCV SXT, 58k miles. A few miles back I felt my brake pedal fading, my wife noticed the pedal fade too. Also had the ABS light come on and off sporadicly. I assumed , maybe incorrectly, I had a bad Master Cylinder, so I swapped it out. I bench bleed the MC before installing and also bleed the whole system to get new fluid throughout. My brake pedal feels good, no fade, however my ABS light stayed on. I had a shop read the codes. Said right rear sensor, I replaced the hub assembly that includes the sensor, taking care with the connection. Disconnected battery to reset light, but light comes back on. I had the ABS diagnostics read again (from another shop), still indicates RR Sensor bad. I swapped the hub assembly again with the upgrade from Advance Auto. Same result, ABS light still on.

Can anyone offer advice? Wiring? How can I check to make sure hte circuit is good? Thanks for any help.

 

I guess I've never had a hub come with a wheel speed sensor. The sensor usually fails because the sensor end gets wet and corrodes so when you get a new sensor it is covered in grease to keep out the moisture.

This is the diagram without traction control




this is the diagram with traction control

 

Thanks Tizzy
My ignorance of the ABS workings maybe the problem. The first shop that read the code gave be a quote to replace the hub assembly/that they said included the ABS wheel Speed Sensor. There price was in the $300 range. I have replaced hub assemblies and knew there was not much to it so I did it myself. Maybe there price included the wiring change too.

Based on your comments, I just did a parts search for an ABS Wheel Speed Sensor. The pictures show it's basically the wiring to the hub. I'll try replacing this and see if that's the issue. The price is in the $40 range.
Also I didn't see any corrosion on the plug to hub, and there was a fair amount of dielectric grease on the connection.

 

You wouldn't see it, it's internal. But yes, you should just need the sensor and you should be fine.

 

take your old sensor with you when you buy the new one as aftermarket hubs dont always use the same sensors, seen some a little longer or shorter than stock.
usually when i buy a hub unit the speed sensor if part of the hub comes with.

 

I replaced the wheel speed sensor, disconnected battery for 10 minutes.

ABS light is still on. ????????????????

 

Then you're looking at an open or short in the harness between the sensor or the ABS module