Circuit/System Testing
IMPORTANT:
It is recommend that Component Testing is performed before Circuit Testing when diagnosing wheel speed sensors.
- Ignition OFF, disconnect the harness connector at the EBCM.
- Ignition ON, test for less than 1 volt between the low reference circuit terminal of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal A2
- RF Sensor circuit terminal A4
- LR Sensor circuit terminal A6
- RR Sensor circuit terminal A8
- If greater than the specified value, test the low reference circuit for a short to voltage. If the circuit tests normal, test or replace the wheel speed sensor.
- Test for less than 1 volt between the signal circuit terminal of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal A1
- RF Sensor circuit terminal A3
- LR Sensor circuit terminal A5
- RR Sensor circuit terminal A7
- If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, test or replace the wheel speed sensor.
- Ignition OFF, test for infinite resistance between the low reference terminal of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal A2
- RF Sensor circuit terminal A4
- LR Sensor circuit terminal A6
- RR Sensor circuit terminal A8
- If less than the specified value, test the low reference circuit for a short to ground. If the circuit tests normal, test or replace the wheel speed sensor.
- Test for infinite resistance between the following signal circuit terminal of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal A1
- RF Sensor circuit terminal A3
- LR Sensor circuit terminal A5
- RR Sensor circuit terminal A7
- If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, test or replace the wheel speed sensor.
- Ignition OFF, disconnect the harness connector at the appropriate wheel speed sensor.
- Ignition OFF, test for less than 2 ohms between the appropriate low reference circuit terminals listed below.
- LF Sensor circuit terminal A2 at the EBCM harness connector and terminal B at the WSS harness connector.
- RF Sensor circuit terminal A4 at the EBCM harness connector and terminal B at the WSS harness connector.
- LR Sensor circuit terminal A6 at the EBCM harness connector and terminal B at the WSS harness connector.
- RR Sensor circuit terminal A8 at the EBCM harness connector and terminal B at the WSS harness connector.
- If greater than the specified value, test the low reference circuit for an open or high resistance. If the circuit tests normal, test or replace the wheel speed sensor.
- Test for less than 2 ohms between the appropriate signal circuit terminals listed below.
- LF Sensor circuit terminal A1 at the EBCM harness connector and terminal A at the WSS harness connector.
- RF Sensor circuit terminal A3 at the EBCM harness connector and terminal A at the WSS harness connector.
- LR Sensor circuit terminal A5 at the EBCM harness connector and terminal A at the WSS harness connector.
- RR Sensor circuit terminal A7 at the EBCM harness connector and terminal A at the WSS harness connector.
- If greater than the specified value, test the signal circuit for an open or high resistance. If the circuit tests normal, test or replace the wheel speed sensor.
- If all circuits test normal, replace the EBCM.