Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the wheel speed sensor or the EBCM, if equipped with ABS.
- Ignition OFF, test for less than 5 ohms between the low reference circuit terminal B and ground.
- 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 rough road signal circuit terminal A.
- If less than the specified range, test the rough road 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 rough road 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
.