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The passenger's temperature setting can be set to
match the driver's temperature setting by pressing the
PASS button and turning off the PASS indicator. When
the passenger's temperature setting is set different than
the driver's setting, the indicator on the PASS button
illuminates and both the driver side and passenger side
temperature displays are shown.
When in defrost mode the passenger temperature
setting cannot be changed.
Automatic Operation
AUTO (Automatic):When automatic operation is active
the system controls 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 changes to
show the current temperature(s) and AUTO is lit on
the display. The current air delivery mode and fan
speed are also displayed for about 5 seconds. When AUTO is selected, the air conditioning
operation and air inlet are automatically controlled.
The air conditioning compressor may run when the
outside temperature is above freezing. The air inlet
will normally be set to outside air. If it is hot
outside, the air inlet may automatically switch to
the recirculate mode to help quickly cool down the
air inside the vehicle. The light on the button
comes on in recirculation.
2. Set the driver's and passenger's temperature. To find your comfort setting, start with a 23°C
(74°F) temperature setting and allow about
20 minutes for the system to regulate. Use the
driver or passenger temperature buttons to adjust
the temperature setting as necessary. If a
temperature setting of 15°C (60°F) is chosen, the
system remains at the maximum cooling setting.
If a temperature setting of 32°C (90°F) is chosen,
the system remains at the maximum heat setting.
Choosing either maximum setting will not cause
the vehicle to heat or cool any faster.
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Do not cover the solar sensor located on the top of the
instrument panel near the windshield. This sensor
regulates air temperature based on sun load. For more
information on the solar sensor, see“Sensors”later in
this section.
To avoid blowing cold air in cold weather, the system
delays turning the fan on until warm air is available. The
length of delay depends on the engine coolant
temperature. Pressing the fan switch overrides this
delay and changes the fan to a selected speed.
Manual Operation
D C(Fan Control): Press these buttons to increase or
decrease the fan speed.
Pressing either fan button while in automatic control
places the fan under manual control. The fan setting
remains displayed and the AUTO light turns off. The air
delivery mode remains under automatic control.
H G(Air Delivery Mode Control): Press these buttons
to change the direction of the airflow in the vehicle.
Repeatedly press either button until the desired mode
appears on the display. Pressing either mode button
while the system is off changes the air delivery mode
without turning the system on. Pressing either mode
button while in automatic control places the mode under
manual control. The air delivery mode setting is displayed and the
AUTO light turns off. The fan remains under automatic
control.
H(Vent):
Air is directed to the instrument panel
outlets.
)(Bi-Level): Air is divided between the instrument
panel and floor outlets. Some air is directed towards the
windshield and side window outlets.
6(Floor): Air is directed to the floor outlets, with some
to the windshield, side window outlets, and second row
floor outlets. In this mode, the system automatically
selects outside air.
-(Defog): This mode clears the windows of fog or
moisture. Air is directed to the windshield, floor outlets,
and side window vents. In this mode, the system turns
off recirculation and runs the air conditioning
compressor unless the outside temperature is close to
freezing. The recirculation mode cannot be selected
while in the defrost mode.
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0(Defrost):This mode removes fog or frost from the
windshield more quickly. Air is directed to the
windshield and side window vents, with some directed
to the floor vents. In this mode, the system
automatically forces outside air into the vehicle and
runs the air conditioning compressor unless the outside
temperature is close to freezing. The recirculation mode
cannot be selected while in the defrost mode.
The passenger temperature control cannot be activated
while in defrost mode. If the PASS button is pressed,
the button indicator flashes three times and will not
work. If the passenger temperature buttons are
adjusted, the driver temperature indicator changes. The
passenger temperature will not be displayed.
If vent, bi-level, or floor mode is selected again, the
climate control system displays the previous
temperature settings.
Do not drive the vehicle until all the windows are clear.
#(Air Conditioning): Press to turn the air
conditioning (A/C) compressor on and off. An indicator
light comes on to show that the air conditioning is on. If this button is pressed when the air conditioning
compressor is unavailable due to outside conditions, the
indicator flashes three times and then turns off. If the air
conditioning is on and the outside temperature drops
below a temperature which is too cool for air
conditioning to be effective, the air conditioning light
turns off to show that the air conditioning mode has
been canceled.
On hot days, open the windows long enough to let hot
inside air escape. This helps to reduce the time it takes
for the vehicle to cool down. It also helps the system to
operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip under the
vehicle while idling or after turning off the engine. This
is normal.
@(Recirculation):
Press to turn the recirculation
mode on. An indicator light comes on to show that the
recirculation is on.
This mode recirculates and helps to quickly cool the air
inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
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The recirculation mode cannot be used with floor, defog,
or defrost modes. If recirculation is selected with one of
those modes, the indicator light flashes three times and
then turns off. The air conditioning compressor also
comes on when this mode is activated. While in
recirculation mode the windows may fog when the
weather is cold and damp. To clear the fog, select either
the defog or defrost mode and increase the fan speed.
The recirculation mode can be turned off by pressing
the outside air button, or by turning off the ignition.
;(Outside Air):Press to turn the outside air mode
on. An indicator light on the button comes on to show
that outside is on. When selected, air from outside the
vehicle circulates throughout the vehicle. The outside
air mode can be used with all modes, but it cannot be
used with the recirculation mode.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger): For vehicles with this
feature, press to turn the defogger on or off.
It automatically turns off several minutes after it has
been activated. The defogger can also be turned off by
turning the engine off. Do not drive the vehicle until all
the windows are clear.
Notice: Do not use a razor blade or sharp object to
clear the inside rear window. Do not adhere
anything to the defogger grid lines in the rear glass.
These actions may damage the rear defogger.
Repairs would not be covered by your warranty.
Heated Mirror: For vehicles with heated outside
rearview mirrors, the mirrors heat to help clear fog or
frost from the surface of the mirror when the rear
window defog button is pressed. See Outside Power
Mirrors on page 3‑57.
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Sensors
The solar sensor, located in the defrost grille, in the
middle of the instrument panel, monitors the solar heat.
Do not cover the solar sensor or the system will not
work properly.
The interior temperature
sensor, located in the
headliner, measures the
temperature of the air
inside the vehicle.
There is also an exterior temperature sensor located
behind the front grille. This sensor reads the outside air
temperature and helps maintain the temperature inside
the vehicle. Any cover on the front of the vehicle could
cause a false reading in the displayed temperature.
The climate control system uses the information from
these sensors to maintain your comfort setting by
adjusting the outlet temperature, fan speed, and the air
delivery mode. The system may also supply cooler air
to the side of the vehicle facing the sun. The
recirculation mode will also be used as needed to
maintain cool outlet temperatures.
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Outlet Adjustment
Use the air outlets located in the center and on the side
of the instrument panel to direct the airflow. Use the
thumbwheels near the air outlets to open or close off
the airflow.
Operation Tips
.Clear away any ice, snow, or leaves from air inlets
at the base of the windshield that could block the
flow of air into the vehicle.
.Keep the path under the front seats clear of
objects to help circulate the air inside of the vehicle
more effectively.
.Use of non‐GM approved hood deflectors can
adversely affect the performance of the system.
Check with your dealer before adding equipment to
the outside of the vehicle.
Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to the
warning lights and gauges could prevent injury.
Warning lights come on when there might be or there is
a problem with one of the vehicle's functions. Some
warning lights come on briefly when the engine is
started to indicate they are working.
Gauges can indicate when there might be or there is a
problem with one of the vehicle's functions. Often
gauges and warning lights work together to indicate a
problem with the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gauges shows there
could be a problem, check the section that explains
what to do. Follow this manual's advice. Waiting to do
repairs can be costly and even dangerous.
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Instrument Panel Cluster
United States Light Duty Premium version shown. Canada, Uplevel, Base, Heavy Duty Clusters similar.
For vehicles with a DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more information.
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Speedometer and Odometer
The speedometer shows the vehicle speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer shows how far the vehicle has been
driven, in either miles (used in the United States) or
kilometers (used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
engine hours, turn the ignition off, press and hold the
reset button for at least four seconds. The hour meter
displays for up to 30 seconds, or until the ignition is
turned on. SeeDIC Operation and Displays (With DIC
Buttons)
on page 4‑49or DIC Operation and Displays
(Without DIC Buttons)on page 4‑56for more
information.
Trip Odometer
The trip odometer shows how far the vehicle has been
driven since the trip odometer was last set to zero.
Press the reset button, located on the instrument panel
cluster next to the voltmeter, to toggle between the trip
odometer and the regular odometer. Holding the reset
button for approximately one second while the trip
odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
See DIC Operation and Displays (With DIC Buttons)
on
page 4‑49or DIC Operation and Displays (Without DIC
Buttons)on page 4‑56for more information.
Tachometer
The tachometer displays the engine speed in
revolutions per minute (rpm). For a description of how
Grade Braking affects vehicle speed while the Tow/Haul
Mode is activated, see “Grade Braking (Allison
Transmission
®)” under Tow/Haul Modeon page 3‑34for more information.
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