Chevrolet Silverado Classic 2007 Owner's Manual page 233

Turn the knob counterclockwise or clockwise
to lower or increase the cabin temperature.
The display will show the temperature setting
decreasing or increasing and an arrow pointing
to the passenger will be displayed under and
to the right of the temperature setting.
The passenger's temperature setting can be
set to match the driver's temperature setting by
pressing and holding the AUTO button for
four seconds. Both the driver and passenger
arrows will be displayed.
Automatic Operation
AUTO (Automatic): When automatic operation
is active the system will control the inside
temperature, the air delivery, and the fan speed.
Use the steps below to place the entire system
in automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will
change to show the current driver's set
temperature, delivery mode and fan speed.
Press the AUTO button again within
five seconds to display the passenger's
set temperature.
If the driver and passenger's temperature
settings are not the same, the opposite side
temperature setting will be displayed for
an additional five seconds. To make the
passenger's temperature the same as
the driver's press and hold the AUTO button
for about four seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will
run when the outside temperature is over
about 40°F (4°C). The air inlet will normally be
set to outside air. If it is hot outside, the air
inlet may automatically switch to recirculate
inside air to help quickly cool down your
vehicle. The light on the button will come on
in recirculation.
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