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Diagnostic 2

WARNING: This page is about a different car, the 2008 Cadillac XLR. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect the harness connector at the TEHC.
  2. Ignition OFF, disconnect the harness connector at the ECM.
  3. Ignition ON, attempt to communicate with the ESC module. Communication should not be available.
    • If communication is established, replace the ECM.
  4. Ignition OFF, disconnect the harness connector at the EBCM.
  5. Ignition ON, attempt to communicate with the ESC module. Communication should not be available.
    • If communication is established, test the following serial data circuits between the ECM and the EBCM for a short between the serial data circuits, short to ground or a short to voltage. If the circuits test normal replace the EBCM.
      • Terminal B9
      • Terminal B12
      • Terminal B9 and B12
  6. Ignition OFF, disconnect the jx168 inline harness connector.
  7. Ignition ON, attempt to communicate with the ESC module. Communication should not be available.
  8. If communication is established, test the following serial data circuits between the headlamp module and the EBCM and the headlamp module and the JX168 inline harness connector for a short between the serial data circuits, short to ground or a short to voltage.
    • Headlamp module terminal 2
    • Headlamp module terminal 5
    • Headlamp module terminal 2 and 5
    • Headlamp module terminal 3
    • Headlamp module terminal 4
    • Headlamp module terminal 3 and 4
    • If the circuits test normal replace the headlamp module.
  9. Ignition OFF, disconnect the harness connector at the TEHC module.
  10. Ignition ON, attempt to communicate with the ESC module. Communication should not be available.
  11. If communication is established, test the following serial data circuits between the TEHC module and the JX168 inline harness connector for a short between the serial data circuits, short to ground or a short to voltage.
    • Terminal 11
    • Terminal 10
  12. If the circuits test normal replace the TEHC module.
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