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Circuit/System Testing

WARNING: This page is about a different car, the 2008 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
  1. Test for less than 1 ohm between the ground circuit terminal 5 of the DLC and ground.
    • If greater than the specified range, test the ground circuit for open/high resistance.
  2. Ignition OFF, disconnect the X2 harness connector at the BCM.
  3. Test for less than 2 ohms on the serial data circuit between terminal 6 of the DLC and terminal 1 of the BCM.
    • If greater than the specified range, test the serial data circuit for open/high resistance.
  4. Ignition OFF, disconnect the X1 and X4 harness connector at the BCM.
  5. Verify a test lamp illuminates between each ground circuit terminal of the BCM listed below and B+.
    • X1 terminal 9
    • X1 terminal 12
    • X2 terminal 13
    • X4 terminal E12
    • If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  6. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal D12 of the BCM and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  7. Ignition ON, test for less than 1 volt between the serial data circuit terminal 6 of the DLC and ground, and terminal 14 of the DLC and ground.
    • If greater than the specified range, test the serial data circuit for a short to voltage.
  8. Test for infinite resistance between the serial data circuit terminal 6 of the DLC and ground, and terminal 14 of the DLC and ground.
    • If less than the specified value, test the serial data circuit for a short to ground.
  9. Test for infinite resistance between the serial data circuits terminal 6 and terminal 14 of the DLC.
    • If less than the specified value, test the serial data circuits for a short between them.
  10. Connect the X1, X2, X3, and X4 harness connectors at the BCM.
  11. Disconnect the appropriate harness connector at the ECM.
    • RPO LZ4/LE5 - X1
    • RPO LY7 - X3
    • RPO HP7 - X3
  12. Attempt to communicate with the vehicle control interface module (VCIM). Communication should not be available.
    • If communication is available, replace the ECM.
  13. Ignition OFF, disconnect the harness connector at the SGCM (RPO - HP7).
  14. Attempt to communicate with the VCIM. Communication should not be available.
    • If communication is available, test the following serial data circuits for a short between the circuits, short to voltage, or a short to ground between the SGCM and the ECM. If the circuits test normal, replace the SGCM.
      • Terminal 11
      • Terminal 23
  15. Ignition OFF, disconnect the harness connector at the TCM.
  16. Attempt to communicate with the VCIM. Communication should not be available.
    • If communication is available, test the following serial data circuits for a short between the circuits, short to voltage, or a short to ground between the TCM and the SGCM. If the circuits test normal, replace the TCM.
      • RPO MH2 - Terminal 12
      • RPO MH2 - Terminal 5
      • RPO MH2 - Terminal 5 and 12
      • RPO MN5 - Terminal 37
      • RPO MN5 - Terminal 38
      • RPO MN5 - Terminal 37 and 38
  17. Ignition OFF, disconnect the harness connector at the EBCM.
  18. Attempt to communicate with the VCIM. Communication should not be available.
    • If communication is available, test the following serial data circuits for a short between the circuits, short to voltage, or a short to ground between the EBCM and the TCM. If the circuits test normal, replace the EBCM.
      • Terminal B12
      • Terminal B9
  19. Ignition OFF, disconnect the X2 harness connector at the power steering control module.
  20. Attempt to communicate with the VCIM. Communication should not be available.
    • If communication is available, test the following serial data circuits for a short between the circuits, short to voltage, or a short to ground between the suspension control module and the terminator resistor. If the circuits test normal, replace the power steering control module.
      • Terminal 1
      • Terminal 2
  21. Ignition OFF, disconnect the X3 harness connector at the VCIM. Attempt to communicate with the BCM. Communication should not be available.
    • If communication is available, test the following serial data circuits for a short between the circuits, short to voltage, or a short to ground between the VCIM and the suspension control module. If the circuits test normal, replace the VCIM.
      • Terminal 9
      • Terminal 8
  22. Ignition OFF, disconnect the X2 harness connector at the BCM.
  23. Ignition ON, test for less than 1 volt between the following serial data circuits of BCM and ground.
    • Terminal 20
    • Terminal 2
    • If greater than the specified range, test the circuit for a short to voltage.
  24. Test for infinite resistance between the following serial data circuits of BCM and ground.
    • Terminal 20
    • Terminal 2
    • If less than the specified value, test the circuit for a short to ground.
  25. Test for infinite resistance between the serial data circuits terminal 20 terminal 2 of the BCM.
    • If less than the specified value, test the serial data circuits for a short between them.
  26. If the circuits test normal, replace the BCM.
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