# Speed sensor?



## fubar008 (Mar 29, 2017)

I have a 2011 cruze 1.8. The ABS light is on along with service traction control. I have searched these forums and I'm almost sure its a speed sensor (I hope anyway). I checked that none were broken or disconnected. Is there a way to determine which one if any is faulty? Thanks for any help


----------



## Robby (Mar 1, 2013)

A tech II or similar code reader will be required to tell you which of the sensors is providing no (or incompatible) information.

The sensor(s) are electromagnets that 'see' a reluctor wheel in the hub.....it spins with the axle. The electromagnet sees a field change as the toothed reluctor passes by it. Sometimes the electromagnets get coated with metallic debris from inside the hub and cannot provide useful info to the ABS computer.

They can be tested individually by unplugging and checking for continuity......good ones have continuity, failed ones have infinite resistance.
If they all have continuity, tech. II testing will tell you which position is the troublemaker.
With any luck you can remove them from the hub, just wipe off the buildup from the tip, and reinstall. 
More often then not though, the bore that the sensor sits in has rusted and is pinching the plastic sensor housing in position. Penetrating oil and gentle twisting and lifting will prove successful.....but I emphasize 'gentle'.......and patience.

Rob


----------



## obermd (Mar 3, 2012)

The Stabilitrak system depends on the ABS sensors to operate. This is why stabilitrak shut down.


----------

