See also:

Engine 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 coo ...

Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the v ...

Reducing Speed While Using Cruise Control
If the cruise control system is already activated: • Move the thumbwheel toward SET/− and hold until the desired lower speed is reached, then release it. • To slow down in small am ...