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)Checking Coolant
The vehicle must be on a level surface when checking the coolant level.
It is normal to see coolant moving in the upper coolant hose return line when
the engine is running.
Check to see if coolant is visible in the coolant surge tank. If the coolant
inside the coolant surge tank is boiling, do ...
Airbag System Check
The airbag system does not need regularly scheduled maintenance or replacement.
Make sure the airbag readiness light is working. See Airbag Readiness Light on page
5-11.
Caution
If an airbag covering is damaged, opened, or broken, the airbag
may not work properly. Do not open or break the ai ...
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 ...