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:
Exterior
The Yukon has a one-piece grille and taller headlights than its sister Tahoe,
with jewel-like bezels and a wider, lower air dam. The rest of the body features
blocky fenders, long rear-quarter win ...
Lamps
Properly working headlamps, taillamps, and brake lamps are important to see and be seen on the road.
• Signs that the headlamps need attention include dimming, failure to light, cracking, or damage ...
What to Do with Used Oil
Used engine oil contains certain elements that can be unhealthy for your skin
and could even cause cancer. Do not let used oil stay on your skin for very long.
Clean your skin and nails with soap ...