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Circuit/System Testing

WARNING: This page is about a different car, the 2008 Chevrolet Malibu Classic. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, test for less than 1.0 ohm of resistance between the DLC ground circuit terminal 5 and ground.
    • If greater than specified, test the ground circuit for open/high resistance.
  2. Disconnect the X2 harness connector at the BCM.
  3. Install a 3Amp fused jumper wire between the BCM serial data circuit terminal 55 and the DLC terminal 1
  4. Ignition ON, attempt to communicate with the BCM. Communication should be available.
    IMPORTANT: Allow communications for 5 seconds after connecting a module with the jumper to determine if communication is interrupted or not.
    • If no communication, test the serial data circuit terminal 55 of the BCM for a short to ground, short to voltage, or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. Ignition OFF, disconnect the X1 harness connector at the BCM.
  6. Ignition OFF, install a 3 Amp fused jumper wire between the BCM serial data circuit terminal 55 and the inflatable restraint sensing and diagnostic module (SDM) terminal 2.
  7. Disconnect the X1 harness connector at the folding top control module, if applicable.
  8. Ignition ON, attempt to communicate with the SDM, communication should not be available.
    • If communication is established, test the folding top control module serial data circuit terminal 2 for a short to voltage or a short to ground. If the circuit tests normal, replace the folding top control module.
  9. Ignition OFF, disconnect the harness connector at the digital radio receiver (DRR), if applicable.
  10. Ignition ON, attempt to communicate with the SDM, communication should not be available.
    • If communication is established, test the DRR serial data circuit terminal 5 for a short to voltage or a short to ground. If the circuit test normal, replace the DRR.
  11. Ignition OFF, disconnect the harness connector at the RCDLR.
  12. Ignition ON, attempt to communicate with the SDM, communication should not be available.
    • If communication is established, test the RCDLR serial data circuit terminal 2 for a short to voltage or a short to ground. If the circuit test normal, replace the RCDLR.
  13. Ignition OFF, disconnect the harness connector at the SDM.
  14. Ignition ON, attempt to communicate with the BCM, communication should not be available.
    • If communication is established, test the SDM serial data circuit terminal 32 for a short to voltage or a short to ground. If the circuit test normal, replace the SDM.
  15. Ignition OFF, remove the 3 Amp fused jumper wire from the BCM terminal 55.
  16. Ignition ON, test for less then 1 volt between the BCM serial data circuit terminal 55 and ground.
    • If greater the specified range, test the serial data circuit for a short to voltage.
  17. Ignition OFF, test for less the 1 ohm between the BCM serial data circuit terminal 55 and ground.
    • If greater than the specified range, test the circuit for a short to ground.
  18. If all circuits test normal, replace the BCM.
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