coaxial

Just got my ABS module back from module masters :-) Works wonders.. Then the ABS light came back on. VAG says the rear left and right speed sensors are not working. Any good universal wheel speed sensors? or what else is out there?

DaveInSaltLake

clean them first!

Christophe du Bornie

Thanks! I cleaned all four and the lights are out. Everything is working fine now. Best regards and thanks to all! Chris.

Christophe du Bornie

To be more specific: All my sensors had a greasy buildup of metallic particles. The rear sensors had enough stuff to bridge the gap between the disc and the sensor tip. Note that the sensors are simply magnets with coils that sense the passing metal teeth machined in the disc rotor. The principle is called the Hall effect and it generates a square or sawtooth signal for the ABS control module. If this waveform is reduced in amplitude by fouling, the module may not distinguish the signal and determine the wheel speed and the error code and malfunction light is activated.