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:
Body Component Lubrication
Lubricate all key lock cylinders, hood hinges, liftgate hinges, and the steel
fuel door hinge unless the components are plastic. Applying silicone grease on weatherstrips
with a clean cloth will m ...
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.
• Read all the ...
Cooling System
If the vehicle has the Duramax® Diesel engine, see the Duramax® Diesel Supplement for more information.
The cooling system allows the engine to maintain the correct working temperature.
5.3 L En ...