See also:

OnStar Personal Identification Number (PIN)
A PIN is needed to access some of the OnStar services, like Remote Door Unlock and Stolen Vehicle Assistance. You will be prompted to change the PIN the first time when speaking with an Advisor. T ...

Parking Brake
To set the parking brake, hold the regular brake pedal down, then push the parking brake pedal down. If the ignition is on, the brake system warning light will come on. See Brake System Warning ...

Engine Overheating
If the vehicle has the Duramax® Diesel engine, see the Duramax Diesel Supplement for more information. The vehicle has several indicators to warn of engine overheating. There is a coolant temperatu ...