Vehicle and Power Issues
OnStar services require a vehicle electrical system, wireless service, and GPS satellite technologies to be available and operating for features to function properly. These systems may not operate if the battery is discharged or disconnected.
See also:
Compass
The vehicle may have a compass display on the Driver Information Center (DIC).
The compass receives its heading and other information from the Global Positioning
System (GPS) antenna, StabiliTrak, ...
Battery Load Management
The vehicle has Electric Power Management (EPM) that estimates the battery's
temperature and state of charge. It then adjusts the voltage for best performance
and extended life of the battery. ...
Safety
Standard safety features include:
Four-wheel antilock brakes
Electronic stability system
Side curtain and side-impact airbags ...