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 ...

Heated Mirrors
For vehicles with heated mirrors: (Rear Window Defogger): Press to heat the mirrors. See “Rear Window Defogger” under Automatic Climate Control System for more information. ...

Using the Universal Remote System
Press and hold the appropriate Universal Remote system button for at least half of a second. The indicator light will come on while the signal is being transmitted. ...