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:
Power Outlets
The accessory power outlets can be used to connect electrical equipment, such
as a cell phone or MP3 player.
There are four accessory power outlets in the following locations: below the
CD slot, ...
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a trailer. See this manual's
Maintenance Schedule or Index for more information. Things that are especially important
in trailer operation are ...
Transferring Service
Push to request account transfer eligibility information. The Advisor can assist in canceling or removing account information. If OnStar receives information that vehicle ownership has changed, OnSta ...