Circuit/System Testing
WARNING: This page is about a different car, the 2011 GMC Acadia, 2011 Chevrolet Traverse, and 2011 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
Liftgate Release Switch Malfunction
- Ignition OFF, disconnect the harness connector at the exterior liftgate control switch.
- Test for less than 1Ω between the ground circuit terminal 2 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, verify the scan tool Liftgate Handle Sw. parameter is Inactive.
- If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.
- Install a 3A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Liftgate Handle Sw. parameter is Active.
- If not the specified parameter, test the signal 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 exterior liftgate control switch.
Liftgate Latch Malfunction
- Ignition OFF, disconnect the L/GATE relay.
- Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 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 87 and ground.
- If the test lamp does not illuminate, test the B+ circuit for an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the control circuit terminal 30 for a short to ground. If the circuit tests normal, test or replace the L/GATE relay.
- Ignition OFF, disconnect the harness connector at the liftgate latch assembly.
- Test for less than 1 Ω between the ground circuit terminal 3 and ground
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect the harness connector at the liftgate latch assembly.
- Ignition ON, connect a 15A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the liftgate latch assembly is activated.
- If the liftgate latch assembly does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the liftgate latch assembly.
- Connect a test lamp between the control circuit terminal 85 and ground.
- Command the liftgate latch to release by pressing and releasing the exterior liftgate control switch. 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 BCM.
- If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- Connect a test lamp between the control circuit terminal 86 and B+.
- Command the liftgate latch to release by pressing and releasing the exterior liftgate control switch. 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 L/GATE relay.