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. ...

Audio System
When using the in-vehicle Bluetooth system, sound comes through the vehicle's front audio system speakers and overrides the audio system. Use the audio system volume knob, during a call, to change the ...

Hands-Free Calling
1. Push System responds: “OnStar ready.” 2. Say “Dial.” System responds: “Please say the name or number to call.” 3. Say the entire number without pausing, including a “1” and the ...