See also:

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 another ce ...

Door Ajar Messages
DRIVER DOOR OPEN This message displays and a chime sounds if the driver door is not fully closed and the vehicle is shifted out of P (Park). Stop and turn off the vehicle, check the door for obstruct ...

Special Application Services
○ Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/ 3,000 mi. ○ Have underbody flushing service performed once a year. ...