2007 GMC SIERRA air condition

Turn the right knob to select the defog or
defrost mode.
-(Defog):This mode clears the windows of fog
or moisture and warm the passengers. The air
is directed to the windshield, oor outlets, and side
window vents.
0(Defrost):This mode removes fog or frost
from the windshield more quickly. A portion of the
air is directed to the windshield and the side
window vents, with some air directed to the oor
vents. The system will automatically force
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.
Rear Window Defogger
If your vehicle has a rear window defogger it uses a
warming grid to remove fog from the rear window.
The rear window defogger will only work when the
ignition is in RUN.
<(Rear):Press this button to turn the rear
window defogger on or off. An indicator light on
the button will come on to let you know that
the rear window defogger is activated.
The rear window defogger will only work when the
ignition is in RUN. The rear window defogger
will stay on for approximately 10 minutes after the
button is pressed, unless the ignition is turned
to ACC or LOCK. The defogger can also be turned
off by pressing the button again or 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 your warranty.
Do not attach a temporary vehicle license,
tape, a decal or anything similar to the
defogger grid.
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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 will always
ow 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 will show 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 will illuminate and both the driver’s
side and passenger’s side temperature displays will
be shown.
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 temperature(s)
and AUTO will be lit on the display. The
current air delivery mode and fan speed will
also be displayed for approximately 5 seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be 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 recirculate
inside air to help quickly cool down your
vehicle. The light on the button will illuminate
in recirculation.
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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. Use the
driver’s or passenger’s temperature buttons 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 load and also turns on your
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.O(On/Off):Press this button to turn off the
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. Recirculation can be selected once you
have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If you adjust the air delivery
mode or temperature settings with the system off,
the display will illuminate briey to show you the
settings and then return to off. Press the on/off
button or the up down arrows on the fan switch, the
defrost button, AUTO button, or the air conditioning
button to turn the system on when it is off.
Manual Operation
You may manually adjust the air delivery mode or
fan speed.
y9 z(Fan):The buttons with the fan symbols
allow you to manually adjust the fan speed.
Press the up arrow to increase fan speed and the
down arrow to decrease fan speed.
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The recirculation mode cannot be used with oor,
defog, or defrost modes. If recirculation is selected
with one of those modes, the indicator light will ash
three times and then turn off. 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 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 this button to turn on
the outside air mode. When this mode is selected,
air from outside the vehicle will circulate
throughout your vehicle. An indicator light on the
button will come on to let you know that it is
activated. The outside air mode can be used
with all modes, but it cannot be used with
the recirculation mode.
Air Conditioning
#
(Air Conditioning):Press this button to turn
the air conditioning (A/C) compressor on and
off. When air conditioning is selected, an indicator
light comes on to let you know that the air
conditioning has been activated.
Pressing this button when the outside temperature
is too cool for air conditioning makes the air
conditioning indicator 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 air conditioning light turns
off to let you know 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 you might notice a small amount of
water dripping underneath the vehicle while idling
or after turning off the engine. This is normal.
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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
clear fog or frost from the windshield.
Use the mode up and down arrows to select the
defog or defrost modes.
-(Defog):Press this button to clear the
windows of fog or moisture and warm the
passengers. This mode directs air to the
windshield, oor outlets, and side window vents.
When this mode is selected, 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 defog mode. Do not drive
the vehicle until all the windows are clear.
0(Defrost):Press this button to remove fog or
frost from the windshield more quickly. This mode
directs a portion of the air to the windshield and side
window vents and some to the oor vents. In this
mode, the system will automatically force outside
air into your vehicle. The recirculation mode cannot
be selected while in the defrost mode. The air
conditioning compressor will run automatically in
this setting, unless the outside temperature is close
to freezing. Do not drive the vehicle until all the
windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):If your vehicle
has this feature, press this button to turn the
defogger on or off. It will automatically turn
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.
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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.
W(Heated Mirrors):If your vehicle has heated
outside rearview mirrors, the mirrors will heat
to help clear fog or frost from the surface of the
mirror when the rear window defog button is
pressed. SeeOutside Power Mirrors on page 176.
Outlet Adjustment
Use the air outlets located in the center and on
the side of the 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 windows.
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 the
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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This light should come on, as a check to show
you it is working, when the ignition is on and the
engine is not running. If the light does not
come on, have it repaired. This light will also
come on during a malfunction in one of two ways:
Light Flashing— A misre condition has
been detected. A misre increases vehicle
emissions and may damage the emission
control system on your vehicle. Diagnosis and
service may be required.
Light On Steady— An emission control
system malfunction has been detected on your
vehicle. Diagnosis and service may be
required.
If the Light is Flashing
The following may prevent more serious damage
to your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount
of cargo being hauled as soon as it is
possibleIf the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do
so, stop the vehicle. Find a safe place to park
your vehicle. Turn the key off, wait at least
10 seconds and restart the engine. If the light
remains on steady, see “If the Light Is On Steady”
following. If the light is still ashing, follow the
previous steps, and see your dealer for service as
soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 493.
The diagnostic system can determine if the
fuel cap has been left off or improperly installed. A
loose or missing fuel cap will allow fuel to
evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the
light off.
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As soon as it is safe to do so, carefully pull your
vehicle over to the side of the road and turn
the ignition off. Check the wiring connection to the
trailer and turn the ignition back on. This
message clears if the trailer is reconnected. This
message also clears if you acknowledge it. If
this message still displays, either your vehicle or
the trailer needs service. See your dealer.
See “Integrated Trailer Brake Control System”
underTowing a Trailer on page 445for more
information.
DRIVER DOOR OPEN
This message displays and a chime sounds if the
driver’s door is not fully closed and the vehicle
is in a drive gear. 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 258. 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 as soon as
possible to avoid damage to the engine.
ENGINE OIL LOW ADD OIL
If your vehicle has an oil level sensor, this
message displays if the oil level in the vehicle is
low. Check the oil level and correct it as
necessary. You may need to let the vehicle cool
or warm up and cycle the ignition to be sure
this message clears.
This message clears itself after 10 seconds, until
the next ignition cycle. SeeEngine Oil (Gasoline
Engine) on page 500for additional information.
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