Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the wheel speed sensor or the electronic brake control module (EBCM) - if equipped with ABS.
- Ignition OFF, test for less than 5 ohms between the low reference circuit and ground.
- Wheel Speed Sensor (LR) low reference circuit terminal B
- Wheel Speed Sensor (RR) low reference circuit terminal A
- Wheel Speed Sensor (LF) low reference circuit terminal B
- Wheel Speed Sensor (RF) low reference circuit terminal A
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
- Ignition ON, test for 4.8-5.2 volts on the signal circuit.
- Wheel Speed Sensor (LR) signal circuit terminal A
- Wheel Speed Sensor (RR) signal circuit terminal B
- Wheel Speed Sensor (LF) signal circuit terminal A
- Wheel Speed Sensor (RF) signal circuit terminal B
- If less than the specified range, test the signal circuit for a short to ground or an open. If the circuit tests normal, replace the ECM.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
- If all circuits test normal, test or replace the wheel speed sensor or EBCM - if equipped with ABS.
IMPORTANT:
If the ABS lamp is illuminated, the ABS system must be diagnosed prior to using this diagnostic procedure. Refer to Diagnostic System Check - Vehicle
.