Diagnostic Aids

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

Inspect the back of the wheel bearing on the encoder surface for metal debris that could cause an erratic reading with the sensor.
Do not use a magnet to clean debris, or damage to the encoder ring may occur.
If two or more wheel speed sensors are inoperative diagnose each wheel speed sensor individually.
If the customer comments that the ABS indicator is ON only during moist environmental conditions: rain, snow, vehicle wash, etc., inspect the wheel speed sensor wiring for signs of water intrusion.