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:
California Perchlorate Materials Requirements
Certain types of automotive applications, such as airbag initiators, seat belt pretensioners, and lithium batteries contained in Remote Keyless Entry transmitters, may contain perchlorate materials.
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Passing Another Vehicle While Using Cruise Control
Use the accelerator pedal to increase the vehicle speed. When you take your foot off the pedal, the vehicle will slow down to the previous set cruise speed. ...
Before Driving Off-Road
○ Have all necessary maintenance and service work completed.
○ Fuel the vehicle, fill fluid levels, and check inflation pressure in all tires,
including the spare, if equipped.
○ ...