Circuit/System Verification
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Ignition OFF, insert the key into the driver's door lock cylinder, turn the key to the LOCK position and hold for greater than 1 second and turn the key to the UNLOCK position and hold for greater than 1 second, all doors should LOCK and UNLOCK while changing between the commanded states.