See also:

Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...

Rear Vision Camera (RVC)
If available, the RVC displays a view of the area behind the vehicle when the vehicle is shifted into R (Reverse). This is displayed on the inside rearview mirror or the navigation screen, if equipped ...

Pairing
A Bluetooth&-enabled cell phone must be paired to the Bluetooth system and then connected to the vehicle before it can be used. See your cell phone manufacturer's user guide for Bluetooth ...