See also:

Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-GMC-8782 (1-800-462-8782), or write: GMC Customer Assistance Center P.O. Box ...

Receiving a Call
When an incoming call is received, the audio system mutes and a ring tone is heard in the vehicle. • Press to answer the call. • Press to ignore a call. ...

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. ...