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Circuit/System Testing

WARNING: This page is about a different car, the 2010 Chevrolet Camaro. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the KR49 headlamp low beam relay.
  2. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
  3. Command the Headlamp Low Beam Command 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 ground. If the circuit tests normal, replace the K9 BCM.
    • If the test lamp is always OFF, test the control circuit for a short to voltage or open/high resistance. If the circuit tests normal, replace the K9 BCM.
  4. If all circuits test normal, test or replace the KR49 headlamp low beam relay.
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