Circuit/System Testing

2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6SECTION Circuit/System Testing
WARNING: This page is about a different car, the 2009 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT: 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 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 range, test the low reference circuit for a short to voltage.
  3. Test for less than 1 volt between the signal circuit terminals of the appropriate sensor listed below and ground.
    • LF Sensor circuit terminal 27
    • RF Sensor circuit terminal 30
    • LR Sensor circuit terminal 16
    • RR Sensor circuit terminal 15
    • If greater than the specified range, test the signal circuit for a short to voltage.
  4. 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.
  5. Test for infinite resistance between the following signal circuit terminals of the appropriate sensor listed below and ground.
    • LF Sensor circuit terminal 27
    • RF Sensor circuit terminal 30
    • LR Sensor circuit terminal 16
    • RR Sensor circuit terminal 15
    • If less than the specified value, test the signal circuit for a short to ground.
  6. Ignition OFF, disconnect the harness connector at the wheel speed sensor.
  7. Test for less than 2 ohms between the appropriate signal circuit terminals listed below.
    • LF Sensor circuit terminals 28 at the EBCM harness connector, and terminal A at the WSS harness connector
    • RF Sensor circuit terminals 17 at the EBCM harness connector, and terminal A at the WSS harness connector
    • LR Sensor circuit terminals 4 at the EBCM harness connector, and terminal A at the WSS harness connector
    • RR Sensor circuit terminals 3 at the EBCM harness connector, and terminal A at the WSS harness connector
    • If greater than the specified range, test the signal circuit for an open or high resistance.
  8. Test for less than 2 ohms between the appropriate low reference circuit terminals listed below.
    • LF Sensor circuit terminals 27 at the EBCM harness connector, and terminal B at the WSS harness connector
    • RF Sensor circuit terminals 30 at the EBCM harness connector, and terminal B at the WSS harness connector
    • LR Sensor circuit terminals 16 at the EBCM harness connector, and terminal B at the WSS harness connector
    • RR Sensor circuit terminals 15 at the EBCM harness connector, and terminal B at the WSS harness connector
    • If greater than the specified range, test the low reference circuit for an open or high resistance.
  9. If all circuits test normal, test or replace the wheel speed sensor (WSS). If the DTC resets, replace the EBCM.
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