See also:

Engine Coolant Heater
The engine coolant heater, if available, can help in cold weather conditions at or below −18°C (0°F) for easier starting and better fuel economy during engine warm-up. Plug in the coolant ...

How to Add Coolant to the Coolant Surge Tank for Gasoline Engines
If the vehicle has a diesel engine, see “Cooling System” in the Duramax Diesel Supplement for the proper coolant fill procedure. WARNING You can be burned if you spill coolant on hot engine part ...

Extended Cab
On vehicles with a sunroof, the sunroof only operates when the ignition is in the ACC/ACCESSORY or ON/RUN or the Retained Accessory Power (RAP) is active. See Retained Accessory Power (RAP) on page ...