Circuit/System Description
WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.
The vehicle rollover sensor (ROS) monitors the vehicle speed signal (VSS) on the GMLAN serial data circuit. If the VSS is marked as invalid or is missing, the ROS will set a diagnostic trouble code (DTC).