Circuit/System Testing

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

Ignition OFF, disconnect the harness connector at the B71R liftgate object sensor - right.
Test for less than 10 Ω between the low reference circuit terminal B and ground.
- If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K39 liftgate module.
Disconnect the harness connector at the B71L liftgate object sensor - left.
Ignition ON, test for 4.75-5.25 V between the signal circuit terminal A and ground.
- If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 liftgate module.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K39 liftgate module.
Test of infinite resistance between the signal circuit terminal B and ground.
- If not the specified value, test the signal circuit for a short to ground.
Test for less than 10 Ω between the signal circuit terminal A at the B71R liftgate object sensor - right and the signal circuit terminal B at the B71L liftgate object sensor - left.
- If greater than the specified range, test the signal circuit for an open/high resistance.
If all circuits test normal, test or replace the appropriate B71 liftgate object sensor.