air conditioning GMC SIERRA CLASSIC 2007 Owners Manual

Mode Control
To change the current mode, select one of the
following:
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to
the instrument panel outlets; then directs most
of the remaining air to the oor outlets. A little air
is directed toward the windshield and the side
window outlets. Cooler air is directed to the upper
outlets and warmer air to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets with a little air directed to the
windshield and the side window outlets.
h(Recirculation):The recirculation mode is
used to recirculate the air inside of your vehicle.
Use this mode to help prevent outside odors
and/or dust from entering your vehicle or to help
cool the air inside of your vehicle more quickly.
Press this button to turn the recirculation mode on
or off. The light on the recirculation button will
illuminate. Recirculation cannot be used in oor,
defog or defrost modes. An indicator on the button
will light up, ash three times and turn off when
recirculation is selected in these modes. The
air-conditioning compressor will also come 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 fan speed.
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Temperature Control
Driver’s Side:The lever on the left side of the
climate control panel is used to raise or lower the
temperature on the driver’s side of the vehicle.
This lever also adjusts the temperature to
the center console outlets, if the vehicle has them.
Passenger’s Side:The lever on the right side
of the climate control panel is used to raise
or lower the temperature on the passenger’s side
of the vehicle.
#(Air Conditioning):Press this button to turn
the air-conditioning system on or off. When
the button is pressed, an indicator light will come
on and the system will begin to cool and
dehumidify the air inside of your vehicle. You may
notice a slight change in engine performance
when the air conditioning compressor shuts off and
turns on again. This is normal.
Defogging and Defrosting
Fog on the inside of the windows is a result of
high humidity (moisture) condensing on the
cool window glass. This can be minimized if the
climate control system is used properly. There are
two modes to choose from to clear fog or frost
from your windshield. Use the defog mode to clear
the windows of fog or moisture and warm the
passengers. Use the defrost mode to remove fog
or frost from the windshield more quickly.
Turn the right knob to select one of the following
modes:
-(Defog):This mode directs the air to the oor
outlets, windshield and the side window outlets.
The air conditioning compressor will run
automatically to dehumidify the air to prevent
window fogging. The recirculation mode cannot be
selected while in the defog mode.
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1(Defrost):This mode directs most of the air to
the windshield and the side window outlets, with
only a little air directed to the oor outlets. The air
conditioning compressor will run automatically
to dehumidify the air to prevent window fogging.
The recirculation mode cannot be selected while in
defrost mode.
Do not drive the vehicle until all the windows are
clear.
Rear Window Defogger
If your vehicle has this feature, the rear window
defogger uses a warming grid to remove fog from
the rear window.
If your vehicle has a sliding rear window, you will
not have a rear window defogger.
<(Rear):Press this button to turn the rear
window defogger on or off. An indicator light in the
button will come on to let you know that the
rear window defogger is activated. This button will
also activate the heated mirrors, if the vehicle
has them.The rear window defogger will automatically turn
off several minutes after the button is pressed.
Pressing the button while the defogger is running
can also turn off the defogger.
W(Mirror):If your vehicle does not have a rear
defogger and has heated mirrors, your vehicle
will have this button to activate the heated mirrors.
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 your warranty.
Do not attach a temporary vehicle license,
tape, a decal or anything similar to the
defogger grid.
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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.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F
(23°C) temperature setting and allow about
20 minutes for the system to regulate. Turn the
driver’s or passenger’s side temperature
knob to adjust the temperature setting as
necessary. If you choose the temperature
setting of 60°F (15°C) the system will remain
at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C)
the system will remain at the maximum
heat setting. Choosing either maximum setting
will not cause the vehicle to heat or cool
any faster.Be careful not to cover the solar sensor
located on the top of the instrument panel
near the windshield. This sensor regulates air
temperature based on sun intensity. It also
turns on the headlamps. For more information
on the solar sensor, see “Sensors” later in
this section.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until
warm air is available. The length of delay
depends on the engine coolant temperature.
Pressing the fan switch will override this delay
and change the fan to a selected speed.
9(Off):Press this button to turn off the entire
climate control system. Outside air will still
enter the vehicle, and will be directed to the oor.
This direction can be changed by pressing the
mode button. The temperature can also be
adjusted using either temperature knob. Press the
up or down arrows on the fan switch, the defrost
button, the AUTO button, or the air conditioning
button to turn the system on when it is off.
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Manual Operation
You may manually adjust the air delivery mode or
fan speed.
w9x(Fan):The switch with the fan symbol
allows you to manually adjust the fan speed. Press
the up arrow to increase fan speed and the
down arrow to decrease fan speed.
Pressing this button when the system is off will
turn the system on.
C(Mode):Press this button to manually change
the direction of the airow in your vehicle;
repeatedly press the button until the desired mode
appears on the display.
If you press the mode button to select an air
delivery mode, the display will change to show you
the selected air mode delivery. The display will then
show the current status of the system. When the
system is turned off, the display will go blank after
displaying the current status of the system.
H(Panel):This mode directs air to the
instrument panel outlets.
)(Bi-Level):This mode directs warmer air to
the oor and cooler air to the instrument panel
outlets.
6(Floor):This mode directs air to the oor
outlets.
-(Defog):See “Defogging and Defrosting” later
in this section.
@(Recirculation):Press this button to limit the
amount of outside air entering your vehicle.
The light on the recirculation button will glow. This
is helpful when you are trying to limit odors
entering your vehicle and for maximum air
conditioning performance in hot weather. Press
this button again to allow outside air to enter
the vehicle. The light on the recirculation button
will go off.
Pressing this button also cancels the auto
recirculation feature. To resume the auto
recirculation function, press the AUTO button.
Each time the vehicle is started, the system will
revert to the auto recirculation function.
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If you select recirculation while in defrost, defog,
or oor, the light in the button will ash and then go
out to let you know that this is not allowed. This
is normal and helps to prevent fogging.
When the weather is cool or damp, operating the
system in recirculation for extended periods of
time may cause fogging of the vehicle’s windows.
To clear the fog, select either defog or front
defrost.
You may also notice that the air condition
compressor will run while in recirculation mode.
This is normal and helps to prevent fogging.
9(Off):Press this button to turn off the entire
climate control system. Outside air will still
enter the vehicle, and will be directed to the oor.
This direction can be changed by pressing the
mode button. The temperature can also be
adjusted using either temperature knob. Press the
up or down arrows on the fan switch, the defrost
button, the AUTO button, or the air conditioning
button to turn the system on when it is off.
Display
If you press the mode button to select an air
delivery mode, the display will change to show you
the selected air delivery mode. After ten seconds,
the display will change to show the driver
temperature setting and the selected mode.
If you press the up or down arrows on the fan
switch, the display will change to show the
selected fan speed. After ten seconds, the display
will change to show the driver temperature
setting and the selected mode.
Whenever you press AUTO, the display will
change to show the following:
The current driver’s set temperature and an
arrow for ve seconds
The current passenger’s set temperature
setting and an arrow for ve seconds
The automatic air delivery mode and fan speed
If the driver’s and passenger’s temperature
settings are the same when AUTO is pressed,
the temperature setting and both arrows will be
displayed for ve seconds along with the automatic
air delivery mode and fan speed. After the
ve second update, the display will change to show
the temperature setting, both arrows, and AUTO.
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Air Conditioning
#
(Air Conditioning):Press this button to turn
the air conditioning (A/C) compressor on and
off. The snowake symbol will appear on
the display when the A/C is on and will turn off
when the air conditioning is off.
Pressing this button when the outside temperature
is too cool for air conditioning will make the
snowake symbol ash three times and then turn
off to let you know the air conditioning mode is
not available. 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 snowake symbol will turn off to let you
know the air conditioning mode has been
canceled.
When air conditioning is selected or in AUTO
mode, the system will run the air conditioning
automatically to cool and dehumidify the air
entering the vehicle. If you select A/C off while in
front defrost, defog or recirculation, the A/C
snowake symbol will turn off, but the A/C
compressor will still run to help prevent fogging.On hot days, open the windows long enough to let
hot inside air escape. This reduces the time it
takes for your vehicle to cool down. Then
keep your windows closed for the air conditioner
to work its best.
On cool, but sunny days while using manual
operation of the automatic system, use bi-level to
deliver warm air to the oor and cooler air to
the instrument panel outlets. To warm or cool the
air delivered, turn the temperature knob to the
desired setting.
In AUTO mode the system will cool and dehumidify
the air inside the vehicle. Also while in AUTO
mode, the system will maximize its performance
by using recirculation as necessary.
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In order to prevent false temperature readings at
startup, the displayed temperature will not
change until the following occurs:
Vehicle speed is above 10 mph (16 kmh) for
5 minutes.
Vehicle speed is above 32 mph (51 kmh) for
2 and a half minutes.
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.
Defogging and Defrosting
You can use either defog or front defrost to clear
fog or frost from your windshield. Use the
defog mode to clear the windows of fog or
moisture. Use the front defrost button to defrost
the front windshield.
-(Defog):Use this setting to clear the windows
of fog or moisture. Press the mode button to
select this setting. This setting will deliver air to
the oor and windshield outlets.
0(Front Defrost):Press the front defrost button
to defrost the windshield. The system will
automatically control the fan speed if you select
defrost from AUTO mode. If the outside
temperature is 40°F (4°C) or warmer, your air
conditioning compressor will automatically run to
help dehumidify the air and dry the windshield.
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Rear Window Defogger
If your vehicle has this feature, the rear window
defogger uses a warming grid to remove fog from
the rear window.
If your vehicle has a sliding rear window, you will
not have a rear window defogger.
<(Rear):Press this button to turn the rear
window defogger on or off. An indicator light in the
button will come on to let you know that the rear
window defogger is activated. This button will also
activate the heated mirrors, if the vehicle has them.
The rear window defogger will automatically turn
off several minutes after the button is pressed.
Pressing the button while the defogger is running
can also turn off the defogger.
W(Mirror):If your vehicle does not have a rear
defogger and has heated mirrors, your vehicle
will have this button to activate them.
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.
Outlet Adjustment
Use the air outlets located in the center and on the
side of your instrument panel to direct the airow.
Operation Tips

Keep the hood and front air inlets free of ice,
snow, or any other obstruction (such as
leaves). The heater and defroster will work
better, reducing the chance of fogging
the inside of your windows.
When you enter a vehicle in cold weather, set
the fan speed to maximum airow for a few
moments before driving. This helps clear
the intake ducts of snow and moisture, and
reduces the chance of fogging the inside
of your window.
Keep the air path under the front seats clear
of objects. This helps air to circulate
throughout your vehicle.
Adding outside equipment to the front of your
vehicle, such as hood-air deectors, may
affect the performance of the heating and air
conditioning system. Check with your
dealer before adding equipment to the outside
of your vehicle.
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DRIVER DOOR AJAR
If the driver’s door is not fully closed, this message
will appear on the display and you will hear a
chime. 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. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the
DIC display. If your vehicle does not have the four
DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear it
from the DIC display.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this
message will appear in the DIC. Turn off the
air conditioning. If the message is still on, or if the
engine coolant temperature gage continues to
rise, pull the vehicle over when it is safe to do so.
SeeEngine Coolant Temperature Gage on
page 256for more information. Stop the vehicle
and let the engine idle in PARK (P) for a few
minutes, or NEUTRAL with the parking brake set
for manual transmissions, to allow the coolant
to reach a safe temperature. This message
will clear when the coolant temperature drops to
safe operating temperature.
ENGINE OVERHEATED
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.
Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 505for more information.
If the engine cooling system reaches unsafe
temperatures for operation, this message
will appear in the DIC and you will hear a chime.
Stop and turn off the vehicle as soon as it is
safe to do so to avoid severe damage. This
message will clear when the engine has cooled to
a safe operating temperature.
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