Diagnostic Aids
WARNING: This page is about a different car, the 2009 GMC Yukon, 2009 Chevrolet Tahoe, 2009 Chevrolet Suburban, and 2009 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
When the circuits operating the lock solenoid are not complete the lock is engaged. When the circuit is completed the lock is disengaged.