Diagnostic Aids
Thoroughly inspect wiring and connectors when diagnosing intermittent DTC(s). This will include the following.
- Removal of protective conduit and inspection to wiring for damage, shorts and contamination.
- Inspection for improperly formed and/or damaged terminals.
- Checking terminal contact (retention force) by using a spare male / female terminal.
- Removal of the terminals from the connectors to check for proper terminal to wire crimp.
If the drivers comments reflect that amber "ABS" warning light is ON only during moist environmental changes (rain, snow, vehicle wash), all wheel speed sensor circuitry should be thoroughly inspected for signs of water intrusion. If the DTC is not current, simulate the effects of water intrusion. Use the following procedure. Spray the suspected area with a 5 percent salt water solution. Then test drive vehicle over various road surfaces such as (bumps, turns, etc.) above 24 km/h (15 mph). If the DTC sets then replace the suspected harness and/or sensor.
When measuring wheel speed sensor resistance insure the vehicle is at room temperature, since resistance will increase with temperature.
Failure to perform the previous steps carefully and fully can result in misdiagnosis, unnecessary component replacement and reoccurrence of the DTC.