Circuit/System Testing

It is recommended that Component Testing is performed before Circuit Testing when diagnosing wheel speed sensors.

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for 0 volts between the low reference circuit terminals of the appropriate sensor listed below and ground.
   • LF Sensor circuit terminal 46
   • RF Sensor circuit terminal 33
   • LR Sensor circuit terminal 37
   • RR Sensor circuit terminal 42
   • If not the specified value, test the low reference circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
3. Test for 0 volts between the signal circuit terminals of the appropriate sensor listed below and ground.
   • LF Sensor circuit terminal 45
   • RF Sensor circuit terminal 34
   • LR Sensor circuit terminal 36
   • RR Sensor circuit terminal 43
   • If not the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
4. Ignition OFF, test for infinite resistance between the low reference terminals of the appropriate sensor listed below and ground.
   • LF Sensor circuit terminal 46
   • RF Sensor circuit terminal 33
   • LF Sensor circuit terminal 37
   • RF Sensor circuit terminal 42
   • If not 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.
5. Test for infinite resistance between the following signal circuit terminals of the appropriate sensor listed below and ground.
   • LF Sensor circuit terminal 45
   • RF Sensor circuit terminal 34
   • LF Sensor circuit terminal 36
   • RF Sensor circuit terminal 43
   • If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, test or replace the wheel speed sensor.
6. If all circuits test normal, replace the EBCM.