LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2011 >> HHR LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Data Communications System >> Diagnostic Information and Procedures >> DTC U1500 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

    NOTE:

    Each control module may need to be disconnected to isolate a circuit fault. Use the schematic to identify the following:

    • Control module locations on the serial data circuits
    • Each control module ignition circuit, ground circuit, and serial data circuit terminals
  1. Ignition OFF, disconnect the harness connectors at the yaw and lateral accelerometer sensor.
  2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 Ω between the low reference circuit terminal 1 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the electronic brake control module (EBCM).
  3. Ignition OFF, verify that a test lamp does not illuminate between the ignition circuit terminal 4 and ground.
    • If the test lamp does illuminate, test the ignition circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
  4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 4 and ground.
    • If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM.
    5. NOTE:

    To ensure that the following test steps work correctly, the harness connector at the steering angle sensor has to be disconnected.

  5. Ignition OFF, disconnect the harness connectors at the EBCM and the steering angle sensor.
  6. Ignition ON, test for less than 1 V between each yaw and lateral accelerometer sensor serial data circuit terminal listed below and ground.
    • Serial data circuit terminal 2
    • Serial data circuit terminal 3
    • If greater than the specified range, test the appropriate serial data circuit for a short to voltage.
  7. Ignition OFF, test for infinite resistance between each yaw and lateral accelerometer sensor serial data circuit terminal listed below and ground.
    • Serial data circuit terminal 2
    • Serial data circuit terminal 3
    • If not the specified value, test the appropriate serial data circuit for a short to ground.
  8. Test for infinite resistance between the yaw and lateral accelerometer sensor serial data circuit terminals 2 and 3.
    • If not the specified value, test the serial data circuits for a short together.
  9. Test for less than 2 Ω in each serial data circuit between the yaw and lateral accelerometer sensor and the EBCM.
    • Serial data circuit terminal 2 at the yaw and lateral accelerometer sensor harness connector and serial data circuit terminal 19 at the EBCM harness connector.
    • Serial data circuit terminal 3 at the yaw and lateral accelerometer sensor harness connector and serial data circuit terminal 18 at the EBCM harness connector.
    • If greater than the specified range, test the appropriate serial data circuit for an open/high resistance.
  10. If all circuits test normal, replace the yaw and lateral accelerometer sensor and verify that the DTC does not reset.
    • If the DTC resets, replace the steering angle sensor.
  11. Verify that the DTC does not reset.
    • If the DTC resets, replace the EBCM.
scientia non olet · About LEMON Manuals