Diagnostic Aids

A thorough inspection of wiring and connectors is important to prevent misdiagnosis. Check for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal-to-wiring connections, or damaged wiring harness. An intermittent may be caused by a poor connection, rubbed-through wire insulation, or a broken wire inside insulation.

If ABS/TCS indicator illuminates only during moist conditions, inspect wheel speed sensor circuitry for signs of water intrusion. Clear DTCs and simulate effects of water intrusion using a saltwater solution. If DTC resets, replace suspect wiring harness.

The following are possible causes of DTC:

• Damaged or missing teeth on one or more wheel speed sensor rings.
• Large grooves or gouges, or foreign material buildup in gaps between wheel speed sensor ring teeth.
• Worn front hub bearing assembly, or inner axle bearing which could allow sensor-to-toothed ring gap to change excessively.