Circuit/System Testing
WARNING: This page is about a different car, the 2006 Chevrolet Monte Carlo and 2006 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the (C4) harness connector at the BCM.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.
- Ignition OFF, disconnect the harness connectors at the components listed below.
- Inside rearview mirror
- Left backup lamp
- Right backup lamp
- Connect a test lamp between the left backup lamp supply voltage circuit terminal A and ground.
- Ignition ON, command the Backup Lamps 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 supply voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM.
If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- Clear the DTC with a scan tool.
- Reconnect each component one at a time and operate the system under the Conditions for Running the DTC. Verify the DTC does not reset as current.
If the DTC resets as current, test or replace the component responsible for setting the DTC.
If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the backup lamp supply voltage circuit terminal 2 C6 for a short to ground.