Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
It is recommended 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 terminals of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal 28
- RF Sensor circuit terminal 17
- LR Sensor circuit terminal 4
- RR Sensor circuit terminal 3
- If greater than the specified value, test the low reference circuit for a short to voltage. If the circuit tests normal, replace the wheel speed sensor
- Test for less than 1 volt between the signal circuit terminals of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal 29
- RF Sensor circuit terminal 6
- LR Sensor circuit terminal 5
- RR Sensor circuit terminal 2
- If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the wheel speed sensor.
- Ignition OFF, test for infinite resistance between the low reference terminals of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal 28
- RF Sensor circuit terminal 17
- LR Sensor circuit terminal 4
- RR Sensor circuit terminal 3
- 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 terminals of the appropriate sensor listed below and ground.
- LF Sensor circuit terminal 29
- RF Sensor circuit terminal 6
- LR Sensor circuit terminal 5
- RR Sensor circuit terminal 2
- 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.
- If all circuits test normal, replace the EBCM.