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)Additional Maintenance and Care
Your vehicle is an important investment and caring for it properly may help to
avoid future costly repairs. To maintain vehicle performance, additional maintenance
services may be required.
It is recommended that your dealer perform these services - their trained dealer
technicians know your ...
Malfunction Indicator Lamp
A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors
the operation of the vehicle to ensure emissions are at acceptable levels, helping
to maintain a clean environment. The malfunction indicator lamp comes on when the
vehicle is placed in ON/RUN, as a check to show ...
Buying New Tires
GM has developed and matched specific tires for the vehicle. The original equipment
tires installed were designed to meet General Motors Tire Performance Criteria Specification
(TPC Spec) system rating. When replacement tires are needed, GM strongly recommends
buying tires with the same TPC Sp ...