Hey Guys,

I got my front left drivers side wheel bearing replaced about a month ago, unfortunately it damaged the ABS sensor. I was able to pull the code C1155 to confirm the sensor was bad. Well I kept using the bad sensor after the bearing was replaced until I received the new one. While using the bad sensor, upon startup and when I began driving, everytime i would brake it felt like I was braking on marbles on this left front wheel. After a few times of braking, the ABS light would come on and the bad braking would go away. I would go through this process each time I would start up the car and drive.

I finally put in the new sensor. Now I have to deal with the braking marbles noise all the time and its dangerous to drive the car this way. The funny part is that the ABS light will no longer turn on, nor am I getting a check engine light. FYI - the magnetic part of the wheel bearing is correctly facing in towards the engine.

Could something be going on with the ABS system? Im pretty lost at this issue. I was thinking of disconnecting the battery and letting the car sit over night to see if it clears anything in the system.

Any ideas?

Thanks!

 

Alex, the first thing that I would question is whether you have the correct sensor installed or not. Next thing is when you say damaged, damaged how? I would also recommend pulling the sensor out to do a quick visual of the sensor to make sure that nothing has happened to the sensor tip (the part next to the bearing) and also to make sure that the teeth inside the bearing are still where they should be. If you can, rotate the wheel through a whole rotation to make sure that all the teeth are there. It could be something as bizarre as there is a tooth or something missing from inside the bearing and what the computer is seeing is no teeth going by the sensor which the computer would see as the tire is locked up. This would cause the computer to ease up on the brake pressure, but then it would see the wheel spinning again shortly thereafter, so, it would then try to put more brake pressure on. This would give you that marble feeling.

You can try disconnecting the battery and seeing if that does anything for you. Just be aware that you may loose the code to your radio, have to reset the programming to your windows, and some other minor stuff. It is all easy stuff to recover from.

 

Chris, I checked both new and old sensor and they look the same. As by the photo you can see the only difference is inside the sensor, has the red plastic insert. The old sensor (photo) looks like it began to get eaten by I believe the faulty wheel bearing.

As for the teeth that you mentioned, I am lost with that. If I removed the speed sensor and look down into the whole, I should spin the wheel and see some teeth?

Thanks for you help.

https://www.dropbox.com/gallery/3654...r/ABS?h=dbd261

 

X2 Jag, if you look deep inside the hole, you would see the teeth. But, that is neither here nor there. If there is a new bearing in there, then the teeth should be good. SInce you talk about damage on the end of the sensor, I am placing money that the installed sensor is toast. It don't take much to mess up the ABS sensors. If you have a new sensor, install the new sensor and then go from there. That should fix your issue.