Automatic Operation
The system automatically controls the fan speed, air delivery, air conditioning, and recirculation to heat or cool the vehicle to the selected temperature.
When the AUTO indicator light is on, the system is in full automatic operation.
To place the system in automatic mode:
1. Press AUTO.
2. Set the temperature. Allow the system time to stabilize. Then adjust the temperature as needed.
To improve fuel efficiency and to cool the vehicle faster, recirculation may
be automatically selected in warm weather. The recirculation light will not come
on. Press the 
to select recirculation;
press it again to select outside air.
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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