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:
Engine Coolant Heater
The engine coolant heater, if available, can help in cold weather conditions
at or below −18°C (0°F) for easier starting and better fuel economy during engine
warm-up. Plug in the coolant ...
Delayed Exit Lighting
Delayed exit lighting illuminates the interior for a period of time after the key is removed from the ignition.
The ignition must be off for delayed exit lighting to work. When the key is removed, in ...
How to Check Lubricant
To get an accurate reading, the vehicle should be on a level surface.
If the level is below the bottom of the fill plug hole, located on the transfer
case, the vehicle will need some lubricant ad ...