See also:

Cellular and GPS Antennas
Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...

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. Wh ...

Vehicle Speed Messages
SELECTED SPEED LIMIT EXCEEDED This message is displayed when the vehicle speed is greater than the set speed. See "Speed Warning" under Driver Information Center (DIC). ...