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)If the Vehicle Is Stuck
Slowly and cautiously spin the wheels to free the vehicle when stuck in sand,
mud, ice, or snow.
If stuck too severely for the traction system to free the vehicle, turn the traction
system off and use the rocking method. See Traction Control/Electronic Stability
Control on page 9-27.
Warning ...
Leaving the Vehicle with the Engine Running (Automatic Transmission)
Warning
It can be dangerous to leave the vehicle with the engine running.
It could overheat and catch fire.
It is dangerous to get out of the vehicle if the shift lever is
not fully in P (Park) with the parking brake firmly set. The vehicle can roll.
Do not leave the vehicle when the engine is ...
Retained Accessory Power (RAP)
These vehicle accessories may be used for up to 10 minutes after the engine is
turned off:
Audio System
Power Windows
The power windows will continue to work for up to 10 minutes or until any door
is opened. The radio will work when the key is in ON/RUN or ACC/ACCESSORY. Once
the key ...