Horn
Pressa 
on the steering wheel pad
to sound the horn.
See also:
Transmission Messages
SERVICE TRANSMISSION
This message displays if there is a problem with the transmission. See your dealer.
SHIFT TO PARK
This message displays when the transmission needs to be shifted to P (Park).
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Online Owner Center
Manage your vehicle (U.S.) at gmc.com. Click on “Owners,” then “Manage My GMC/Owners Login.”
Information and services customized for your specific vehicle — all in one convenient place.
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Radio(s)
Radio with CD, DVD, and USB Port
: Press to turn the system on and off. Turn to increase or decrease the volume.
BAND: Press to choose between FM, AM, or XM™, if equipped.
: Select radio stat ...