Using the “Dial” or “Call” Command
1. Press and hold 
for two seconds.
2. Say “Dial” or “Call.” 3. Say the entire number without pausing, or say the name tag.
Once connected, the person called will be heard through the audio speakers.
See also:
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.
...
Horn
Pressa on the steering wheel pad
to sound the horn. ...
Anti-theft Alarm System
On vehicles with an anti-theft alarm system, to activate the system:
• Press on the Remote Keyless Entry (RKE) transmitter or the power door lock switch when any door is open.
The security ligh ...