Circuit/System Description
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.
The liftgate module (LGM) receives an input from the liftglass ajar switch. The ajar switch is normally open when the liftglass is fully closed. When the liftglass is opened, the ajar switch contact closes providing a path to ground. The driver information center (DIC) illuminates the Rear Access Open message when the liftglass is open.