See also:

How OnStar Service Works
Automatic Crash Response, Emergency Services, Crisis Assist, Stolen Vehicle Assistance, Vehicle Diagnostics, Remote Door Unlock, Roadside Assistance, Turn-by-Turn Navigation, and Hands-Free ...

Lockout Protection
If the power door lock switch is pressed when the key is in the ignition and a door is open, all the doors will lock and only the driver door will unlock. If the doors are closed, they can b ...

Brake Assist (Except CTS-V)
This vehicle has a brake assist feature designed to assist the driver in stopping or decreasing vehicle speed in emergency driving conditions. This feature uses the stability system hydrauli ...