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 cellular area.
See also:
Total Weight on the Vehicle's Tires
Inflate the vehicle's tires to the upper limit for cold tires. These numbers can be found on the Certification label or see Vehicle Load Limits on page 9‑10 for more information. Do not go over ...
Driving on Grades
Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might have to be used so much that they would get hot and no ...
Transportation Options
Warranty service can generally be completed while you wait. However, if you are unable to wait, GM helps to minimize inconvenience by providing several transportation options. Depending on the circums ...