2010 GMC SIERRA DENALI air conditioning

9(Fan Control):Turn clockwise or counterclockwise
to increase or decrease the fan speed. Turn the knob all
the way counterclockwise to turn the front system off.
Air Delivery Mode Control : Turn clockwise or
counterclockwise to change the direction of the airflow
inside the vehicle. The knob can be positioned between
two modes to select a combination of those modes.
Select from the following:
H (Vent) : Air is directed to the instrument panel outlets.
) (Bi-Level) : Air is divided between the instrument
panel and floor outlets.
6 (Floor) : Air is directed to the floor outlets, with some
air directed to the windshield and side window outlets.
In this mode, the system automatically selects outside
air. Recirculation cannot be selected in floor mode.
- (Defog) : This mode clears the windows of fog or
moisture. Air is directed to the windshield, floor outlets,
and side window vents. 0
(Defrost) : This mode removes fog or frost from the
windshield more quickly. Air is directed to the
windshield and the side window vents, with some air
directed to the floor vents. The system automatically
forces outside air into the vehicle.
The recirculation mode cannot be selected in the defog
or defrost mode. When either mode is selected, the
system runs the air conditioning compressor, unless the
outside temperature is close to freezing.
Do not drive the vehicle until all the windows are clear.
:(Outside Air): Press to turn the outside air mode
on. An indicator light comes on to show that outside air
is on. In this mode outside air circulates throughout the
vehicle. The outside air mode can be used with all
modes, but it cannot be used with the
recirculation mode.
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?(Recirculation):Press to turn the recirculation
mode on. An indicator light comes on to show that
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.
The recirculation mode cannot be used with floor, defog
or defrost modes. If recirculation is selected with one of
these modes, the indicator light flashes three times and
then turns off. 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.
# (Air Conditioning) : Press to turn the air conditioning
system on or off. An indicator light comes on to show
that the air conditioning is on. The air conditioning can
be selected in any mode as long as the fan switch is on.
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.Rear Window Defogger
For vehicles with a rear window defogger, a warming
grid is used to remove fog from the rear window.
< (Rear) : Press to turn the rear window defogger on
or off. An indicator light on the button comes on to show
that the rear window defogger is on.
The rear window defogger only works when the ignition
is in ON/RUN. The rear window defogger stays on for
approximately 10 minutes after the button is pressed,
unless the ignition is turned to ACC/ACCESSORY or
LOCK/OFF. The defogger can also be turned off by
turning off the engine.
Notice: Do not use anything sharp on the inside of
the rear window. If you do, you could cut or damage
the warming grid, and the repairs would not be
covered by the vehicle warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
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Dual Automatic Climate Control
System
The heating, cooling, and ventilation in the vehicle can
be controlled with this system. The vehicle also has a
flow-through ventilation system described later in this
section.
A. Driver and PassengerTemperature Controls
B. Fan Control
C. AUTO
D. Defrost E. Recirculation F. Outside Air G. Air Delivery Mode
Control
H. Display
I. Power Button
J. Rear Window Defogger
K. Air Conditioning L. PASS (Passenger)
O(On/Off): Press to turn the climate control system on
or off. Outside air still enters the vehicle, and is directed
to the floor. This direction can be changed by pressing
the mode button. Recirculation can be selected once
you have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If the air delivery mode or
temperature settings are adjusted with the system off,
the display illuminates briefly to show the settings and
then returns to off. The system can be turned back on
by pressing either
O,D,C,#, the defrost or the
AUTO button.
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Driver and Passenger Side Temperature
Controls
The driver and passenger side temperature buttons are
used to adjust the temperature of the air coming
through the system on the driver or passenger's side of
the vehicle. The temperature can be adjusted even if
the system is turned off. This is possible since outside
air always flows through the system as the vehicle is
moving forward unless it is set to recirculation mode.
See“Recirculation” later in this section.
Press the + or −buttons to increase or decrease the
cabin temperature. The driver side or passenger side
temperature display shows the temperature setting
decreasing or increasing.
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.
4-22

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.
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.
4-24

@(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.
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 3‑40.
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DRIVER DOOR OPEN
This message displays and a chime sounds if the driver
door is not fully closed and the vehicle is shifted out of
P (Park). Stop and turn off the vehicle, check the door
for obstructions, and close the door again. Check to see
if the message still appears on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage
on page 4‑37.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off. When
the coolant temperature returns to normal, the air
conditioning compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible to
avoid damage to the engine.
ENGINE OIL HOT IDLE ENGINE
This message displays when the engine oil becomes
hotter than the normal operating temperature. Stop and
allow the vehicle to idle until it cools down. See Engine
Coolant Temperature Gage
on page 4‑37.
ENGINE OVERHEATED IDLE ENGINE
Notice: If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If an
overheat warning appears on the instrument panel
cluster and/or DIC, stop the vehicle as soon as
possible. See Engine Overheating
on page 6‑34for
more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down. See Engine Coolant
Temperature Gage on page 4‑37.
See Overheated Engine Protection Operating Mode
on
page 6‑37for information on driving to a safe place in
an emergency.
ENGINE OVERHEATED STOP ENGINE
Notice: If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If an
overheat warning appears on the instrument panel
cluster and/or DIC, stop the vehicle as soon as
possible. See Engine Overheating
on page 6‑34for
more information.
This message displays and a chime sounds if the
engine cooling system reaches unsafe temperatures for
operation. Stop and turn off the vehicle as soon as it is
safe to do so to avoid severe damage. This message
clears when the engine has cooled to a safe operating
temperature.
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If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. SeeTowing a Trailer on page 5‑42.
If the overheat warning is displayed with no sign of
steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let the
engine idle. If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down. Also,
see
“Overheated Engine Protection Operating Mode”
later in this section.
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