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Circuit/System Testing

WARNING: This page is about a different car, the 2011 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the E8S rear compartment courtesy lamp.
  2. Test for less than 5 Ω between the ground circuit terminal 2 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal 1 and ground.
  4. Command the Cargo Lamp ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
    • If the test lamp is always OFF, test the control circuit for a short to round or open/high resistance. If the circuit tests normal, replace the K9 BCM.
  5. If the all circuits test normal, replace the E8S rear compartment courtesy lamp.
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