Circuit/System Description
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The Shock Sensor is a component of the Content Theft Deterrent system which monitors the vehicle for shock impacts. The shock sensor provides an alarm signal to the body control module (BCM) in the attempt that the vehicle is being tampered with. The sensor ground is controlled through a switched ground output from the BCM. By providing ground from the BCM the sensor is powered-up and activated.