Conditions for Setting the DTC
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The BCM, driver door lock and side window switch, or passenger door lock and side window switch detects a short to ground, short to voltage, or open on the courtesy lamp voltage supply circuit.