GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 243

The vehicle may have a front ashtray located near the
center of the instrument panel. Pull on the door to open
it. The ashtray may have a cigarette lighter.
To remove the ashtray, open the door and pull the
ashtray bin toward you. To replace the ashtray, insert
the ashtray bin inside the ashtray door and press down
until it engages. To use the cigarette lighter, push it in
all the way, and let go. When it is ready for use, the
lighter pops back out.
With this system the heating and ventilation can be
controlled.
A. Fan Control
B. Temperature Control
C. Air Delivery Mode Control
counterclockwise to increase or decrease the
temperature inside the vehicle.
Turn clockwise or
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