Circuit/System Testing
WARNING: This page is about a different car, the 2010 Saturn Outlook, 2010 GMC Acadia, 2010 Chevrolet Traverse, and 2010 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
Before beginning this circuit/system test, review the schematic to verify:
- Park lights the vehicle is equipped with.
- Component locations on the park lighting control circuit
- Each component's control and ground circuit terminals
- Ignition OFF, disconnect the PRK LAMP relay.
- Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
- If the test lamp illuminates, test the control circuit for a short to voltage.
- Verify that a test lamp illuminates between the B+ circuit terminal 85 and ground.
- If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
- Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
- If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
- Disconnect the harness connector at an inoperative park lamp.
- Test for less than 5 Ω between the ground circuit terminal and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect the harness connector at the park lamp.
- Connect a 10 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the park lamp is activated.
- If the park lamp does not activate and the jumper wire fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the park lamp.
- If the park lamp does not activate and the jumper wire fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the park lamp.
- Connect a test lamp between the B+ circuit terminal 85 and the control circuit terminal 86.
- Command the Park 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 control circuit for a short to ground. If the circuit tests normal, replace the BCM.
- If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the PRK LAMP relay.