Engine Coolant Heater
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.
An internal thermostat in the plug-end of the cord may exist which will prevent engine coolant heater operation at temperatures above −18°C (0°F).
If the vehicle has a diesel engine, see the Duramax Diesel supplement for more information.
See also:
Rear Window Wiper/Washer
The rear wiper and rear wash button is located on the instrument panel below the climate control system.
(Rear Wiper): Press to turn the rear wiper on and off. The wiper speed cannot be changed.
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Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote
Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously
for five days. After five days, ...





