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:
Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many parts have to be of top
quality and work well together if the vehicle is to have really good braking. The
vehicle was designed and tested with ...
Hill Start Assist (HSA)
This vehicle has a Hill Start Assist (HSA) feature, which may be useful when the vehicle is stopped on a grade. This feature is designed to prevent the vehicle from rolling, either forward or rearward ...