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. ...

How to Detect a Tamper Condition
If  is pressed and the horn sounds, an attempted break-in occurred while the system was armed. If the alarm has been activated, a message will appear on the DIC. See Anti-theft Alarm ...

Engine Drive Belt Routing
4.2L V6 Engine 5.3L V8 Engine ...