Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

Inspect the vehicle for proper wheel alignment. Ensure the vehicle does not pull toward the left or right while driving straight forward on a level surface.
Communicate with the customer to determine the conditions under which the message center displays the Service Stability System message. Learning the conditions under which the DTC sets may help you duplicate the failure.
Use the Snapshot function on the scan tool in order to assist you in locating an intermittent malfunction.