Circuit/System Verification
WARNING: This page is about a different car, the 2011 GMC Acadia, 2011 Chevrolet Traverse, and 2011 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
Ignition ON, observe the scan tool Wheel Speed Sensor parameters while spinning the wheels. The readings should be analog to the wheel speeds.