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)Emergency
With Automatic Crash Response, the OnStar system can automatically connect to
an OnStar Emergency Advisor. The built-in system can automatically connect to help
in certain crashes.
Press to connect to an OnStar Emergency
Advisor. GPS technology is used to identify the vehicle location and ca ...
How to Add Coolant to the Coolant Surge Tank
Caution
This vehicle has a specific coolant fill procedure. Failure to
follow this procedure could cause the engine to overheat and be severely damaged.
If no problem is found, check to see if coolant is visible in the coolant surge
tank. If coolant is visible but the coolant level is not at t ...
Exit Lighting
If the dome lamps are in the DOOR position, they come on automatically when the
key is removed from the ignition. The exterior lamps and dome lamps remain on after
the door is closed for a set amount of time, then automatically turn off.
The headlamps, parking lamps, and back-up lamps will turn ...