2008 CHEVROLET SILVERADO Owners Manual

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
remains at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C),
the system remains 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. 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.O(On/Off):Press this button to turn off the climate
control system. 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. 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.
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Manual Operation
The air delivery mode or fan speed can be manually
adjusted.
DC(Fan):These buttons let you manually adjust the
fan speed. Press
Dto increase fan speed andCto
decrease fan speed.
Pressing either fan button while the system is off turns
the system on. 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.
HG(Mode):PressHandGto manually change the
direction of the airow 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 directed partly to the instrument
panel outlets and to the oor outlets. A little air is
directed towards the windshield and side window outlets.
Cooler air is directed to the upper outlets and warmer
air to the oor outlets.
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 will
automatically select outside air.
-(Defog):See “Defogging and Defrosting” later in
this section.
@(Recirculation):Press this button to turn the
recirculation mode on. When the button is pressed, an
indicator light comes on.
This mode keeps outside air from entering the vehicle.
It can be used to reduce outside air and prevent
odors from entering the vehicle. Recirculation may also
help cool the air inside the vehicle more quickly once
the temperature inside the vehicle is less than the
outside temperature.
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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 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 this button to turn on the
outside air mode. When this mode is selected, air from
outside the vehicle circulates throughout the vehicle.
An indicator light on the button comes on to show
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
show 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 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 underneath
the vehicle while idling or after turning off the engine.
This is normal.
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Sensors
The solar sensor, located
in the defrost grille, in the
middle of the instrument
panel, monitors the
solar radiation. 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 on the rearview mirror.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
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
HandGto 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.
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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 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: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 2-61.
Outlet Adjustment
Use the air outlets located in the center and on the side
of the instrument panel to direct the airow. Use the
thumbwheels near the air outlets to open or close off
the airow.
Operation Tips

Clear away any ice, snow, or leaves from air inlets
at the base of the windshield that could block the
ow 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 deectors can
adversely affect the performance of the system.
Check with your dealer/retailer before adding
equipment to the outside of your vehicle.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages on
your vehicle. The pictures help to locate them.
Warning lights and gages 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 gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As the
details show on the next few pages, some warning lights
come on briey when you start the engine just to let you
know they are working. If you are familiar with this
section, you should not be alarmed when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages and
warning lights work together to let you know when there
is a problem with your vehicle.
When one of the warning lights comes on and stays on
as you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s
advice. Waiting to do repairs can be costly and even
dangerous. So please get to know your vehicle’s
warning lights and gages. They can be a big help.
Your vehicle also has a Driver Information Center (DIC)
that works along with warning lights and gages.
SeeDIC Warnings and Messages on page 3-66for
more information.
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Instrument Panel Cluster
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You will know how fast
you are going, about how much fuel you have and many other things you will need to know to drive safely and
economically. If your vehicle has the DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more
information.United States Light Duty Premium version shown. Canada, Uplevel, Base, Heavy Duty Clusters similar.
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Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your 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
will be displayed for up to 30 seconds, or until the
ignition is turned on. SeeDIC Operation and Displays
(With DIC Buttons) on page 3-57orDIC Operation
and Displays (Without DIC Buttons) on page 3-63for
more information.
Trip Odometer
The trip odometer can tell you how far your vehicle
has been driven since you last set the trip odometer
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.
SeeDIC Operation and Displays (With DIC Buttons)
on page 3-57orDIC Operation and Displays (Without
DIC Buttons) on page 3-63for more information.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm). See “Grade Braking
(Allison Transmission
®)” underTow/Haul Mode on
page 2-34for more information.
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