Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. 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 liftgate handle switch.
- Test for less than 1 Ω between the ground circuit terminal B 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 A for a short to ground. If the circuit tests normal, replace the body control module.
- Install a 3 A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool Liftgate Handle Sw parameter is Active.
- If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the body control module.
- If all circuits test normal, test or replace the liftgate handle switch.
Liftgate Release Malfunction
- Ignition OFF, disconnect the harness connector at the liftgate latch assembly.
- Test for less than 5 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 a test lamp between the control circuit terminal 1 and ground.
- Ignition ON, command the liftgate latch assembly to UNLATCH by pressing the liftgate handle switch. The test lamp should illuminate during the UNLATCH command
- If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the fuse block-underhood.
- If the test lamp is always OFF and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the liftgate latch assembly
- If the test lamp is always OFF and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal, refer to Underhood Fuse Block Test.
- If all circuits test normal, test or replace the liftgate latch assembly.
Underhood Panel Fuse Block Test
- Ignition OFF, disconnect the X7 harness connector at the body control module.
- Connect a 10 A fused jumper wire between the control circuit terminal 3 and B+, briefly connect a jumper wire between the control circuit terminal 1 and ground. Verify the liftgate latch is activated.
- If the liftgate latch does not activate, test either control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the fuse block-underhood.
- If all circuits test normal, replace the body control module.