Emergency
With Automatic Crash Response, the built-in system can automatically connect to help in a crash even if you cannot ask for it.
Push 
to connect to an Emergency Advisor. GPS technology is used to identify the vehicle location and can provide critical information to emergency personnel. The Advisor is also trained to offer critical assistance in emergency situations.
See also:
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps
A. Low-Beam Headlamp
B. High-Beam Headlamp
C. Sidemarker Lamp
D. Park/Turn Signal Lamp
To replace one of these bulbs:
1. Turn the tire to reach the access port cap located in the front of wheel ...
Using Voice Commands During a Planned Route
Cancel Route
1. Push . System responds:
“OnStar ready,” then a tone. Say “Cancel route.” System responds: “Would you like to cancel route directions to your destination?” 2. Say “Yes. ...
Following Distance
Stay at least twice as far behind the vehicle ahead as you would when driving the vehicle without a trailer.
This can help to avoid situations that require heavy braking and sudden turns. ...