Horn
Pressa 
on the steering wheel pad
to sound the horn.
See also:
Park Brake and P (Park) Mechanism Check
WARNING
When you are doing this check, the vehicle could begin to move. You or others
could be injured and property could be damaged. Make sure there is room in front
of the vehicle in case it be ...
Door Locks
There are several ways to lock and unlock the vehicle.
From outside, use the Remote Keyless Entry (RKE) transmitter or the key in the driver door.
From inside, use the power door locks or the manual ...
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.
...