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:
Using Voice Commands During a Planned Route
Cancel Route
1. Push X. System responds: “OnStar ready,” then a tone. Say “Cancel route.”
System responds: “Would you like to cancel route directions to your destination?”
2. Say “Ye ...
Tire Pressure
Tires need the correct amount of air pressure to operate effectively.
Notice: Neither tire underinflation nor overinflation is good.
Underinflated tires, or tires that do not have enough air, can re ...
Hoses
Hoses transport fluids and should be regularly inspected to ensure that there are no cracks or leaks.
With a multi-point inspection, your dealer can inspect the hoses and advise if replacement is nee ...





