Circuit/System Verification
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
Ignition ON, verify the scan tool LF Key Cylinder Lock Switch parameter cycles between Idle and Unlock while turning the driver door lock cylinder to the unlock position with the vehicle key.