See also:

How the System Works
The SBZA symbol lights up in the side mirrors when the system detects a vehicle in the side blind zone, indicating it may be unsafe to change lanes. Before making a lane change, check the SBZA dis ...

Unable to Connect to OnStar Message
If there is limited cellular coverage or the cellular network has reached maximum capacity, this message may come on. Push to try the call again or try again after driving a few miles into ...

Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF in each shift lever position. The ignition should turn to LOCK/OFF only when the shift lever is in P (Park). ...