ABS Wheel Speed Sensors
ABS-equipped vehicles contain wheel speed sensors mounted on the suspension and steering knuckles. The tone rings for these speed sensors spin with the hub or CV axle.
A loose bearing can cause the ring to wobble and damage the wheel speed sensor's tip. This damage results in an ABS warning light.
Scan the controller for fault codes. If fault codes indicate a defective sensor, inspect the harness, wiring, controller, and wheel speed sensor before replacement. Sometimes mud or road debris gets into the gap or between the tone sprockets creating a problem with the signal.
Inspect the wheel bearings by grasping the tire at the top and bottom and rocking it back and forth. Excessive play indicates a loose wheel bearing. Faulty wheel bearings make a growling or whining sound that increases with vehicle speed and while turning.