2009 GMC SIERRA air condition

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.
?(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 oor, defog
or defrost modes. If recirculation is selected with one of
these modes, the indicator light ashes 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
ow-through ventilation system described later in
this section.
A. Driver and Passenger
Temperature Controls
B. Fan Control
C. AUTO
D. Defrost
E. Recirculation
F. Outside AirG. 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 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 the air delivery mode or
temperature settings are adjusted with the system
off, the display illuminates briey 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 ows 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.
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.
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6(Floor):Air is directed to the oor outlets, with
some to the windshield, side window outlets, and
second row oor 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, oor 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 oor 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.
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 ashes 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.
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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 oor,
defog, or defrost modes. If recirculation is selected
with one of those modes, the indicator light ashes
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 Mirrors: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. SeeOutside Power Mirrors
on page 2-59.
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Charging System Light
This light comes on briey
when the ignition key is
turned to START, but
the engine is not running,
as a check to show it
is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it
stays on, or comes on while driving, there could be a
problem with the charging system. A charging system
message in the Driver Information Center (DIC) can also
appear. SeeDIC Warnings and Messages on page 3-66
for more information. This light could indicate that
there are problems with a generator drive belt, or that
there is an electrical problem. Have it checked right
away. If the vehicle must be driven a short distance with
the light on, turn off accessories, such as the radio
and air conditioner.
Voltmeter Gage
For vehicles with a
voltmeter gage, this gage
indicates the battery
voltage when the ignition
is turned on.
When the ignition is on, this gage indicates the
battery voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage can
transition from a higher to lower or a lower to higher
reading. This is normal. If the vehicle is operating
outside the normal operating range, the charging system
light comes on. SeeCharging System Light on
page 3-41for more information. The voltmeter gage
may also read lower when in fuel economy mode.
This is normal.
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Readings outside the normal operating range can also
occur when a large number of electrical accessories
are operating in the vehicle and the engine is left idling
for an extended period. This condition is normal since
the charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
The vehicle can only be driven for a short time with the
readings outside the normal operating range. If the
vehicle must be driven, turn off all accessories, such as
the radio and air conditioner.
Readings outside the normal operating range indicate a
possible problem in the electrical system. Have the
vehicle serviced as soon as possible.Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle is
driven with the parking brake engaged, a chime sounds
when the vehicle speed is greater than 5 mph (8 km/h).
The vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking,
both parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake uid.
SeeBrakes on page 5-40for more information.
United States
Canada
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If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by the vehicle warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of the
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a
required Emission Inspection/Maintenance test.
SeeAccessories and Modifications on page 5-4.This light comes on during a malfunction in one of
two ways:
Light Flashing:A misre condition has been detected.
A misre increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer for service as soon
as possible.
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