GATE AJAR Indicator
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The instrument panel cluster (IPC) illuminates the GATE AJAR indicator when the body control module (BCM) detects that the liftgate or liftglass is ajar or open. The IPC receives a LAN message from the BCM requesting illumination. If the vehicle is in the forward or reverse gear position, the BCM activates an audible warning.