The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below -18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting.

It is shipped from the factory with a tie holding it in place. Use care in removing the tie so that the cord is not damaged.
Check the heater cord for damage. If it is damaged, do not use it. See your dealer for a replacement. Inspect the cord for damage yearly.
Warning
Improper use of the heater cord or an extension cord can damage the cord and may result in overheating and fire.
Failure to use the recommended extension cord in good operating condition, or using a damaged heater or extension cord, could make it overheat and cause a fire, property damage, electric shock, and injury.
Keep the cord away from any moving parts.
If you do not it could be damaged.
The length of time the heater should remain plugged in depends on several factors. Ask a dealer in the area where you will be parking the vehicle for the best advice on this.
Starting the Engine
Retained Accessory Power (RAP)Starter Switch Check
Warning
When you are doing this inspection, the vehicle could move suddenly.
If the vehicle moves, you or others could be injured.
Before starting this check, be sure there is enough room around the vehicle.
Apply both the parking brake and the regular brake.Do not use the accelerator
pe ...
Auxiliary Devices
Using the Auxiliary Input Jack
Settings menus and functions may vary depending on vehicle options.
If equipped, the auxiliary input jack in the center stack can be used to connect
external audio devices such as an iPod®, iPhone®, MP3 player, CD player, and other
supported devices for use as an ...
OnStar Additional Information
Transferring Service
Press to request account transfer
eligibility information. The Advisor can assist in canceling or removing account
information.
Selling/Transferring the Vehicle
Call 1-888-4-ONSTAR immediately to terminate your OnStar services if the vehicle
is disposed of, sold, trans ...