Call Waiting
Call waiting must be supported on the cell phone and enabled by the wireless service carrier.
• Press 
to answer an incoming call when another call is active. The original call is placed on hold.
• Press again to return to the original call.
• To ignore the incoming call, no action is required.
• Press 
to disconnect the current call and switch to the call on hold.
See also:
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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Vehicle Personalization
The audio system controls are used to access the personalization menus for customizing
vehicle features.
CONFIG (Configuration): Press to access the Configuration Settings Menu.
MENU/SELECT Knob: ...
Electronic Range Select (ERS) Mode
ERS or manual mode allows for the selection of the range of gear positions. Use
this mode when driving down hill or towing a trailer to limit the top gear and vehicle
speed.
To use this feature:
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