2007 GMC SIERRA CLASSIC climate control

W(Defog):Airow is delivered through the oor
outlets, the windshield defroster outlets, and
the side window defroster outlets. The air ow can
be divided between oor and defrost depending
upon where the knob is placed between the
settings.
1(Defrost):This setting directs most air
through the windshield defroster outlets, side
window defroster outlets, and some through the
oor outlets.
Dual Climate Control System
With this system you can control the heating,
cooling, and ventilation for your vehicle.
Fan Control
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan
speed. Turn the knob to the off position to turn
off the fan. If the knob is in off, outside air will still
enter the vehicle and will be directed based on
the position of the mode knob. The temperature
can also be adjusted using the temperature levers.
Turn the right knob clockwise or counterclockwise
to direct the airow inside of your vehicle.
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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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Dual Automatic Climate Control
System
With this system, you can control the heating,
cooling, and ventilation in your vehicle. Your
vehicle also has a ow-through ventilation system
described later in this section.
You can select different climate control settings for
the driver and passengers.
Driver’s Side Temperature Knob
The driver’s side knob is used to adjust the
temperature of the air coming through the system
on the driver’s side. 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.
Turn the knob counterclockwise or clockwise to
lower or increase the cabin temperature. The
display will show the temperature setting
decreasing or increasing and an arrow pointing to
the driver will be displayed under and to the
left of the temperature setting.
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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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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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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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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and
you pull a trailer with your vehicle, carbon
monoxide (CO) could come into your
vehicle. You cannot see or smell CO. It
can cause unconsciousness or death. See
Engine Exhaust on page 174. To maximize
your safety when towing a trailer:
Have your exhaust system inspected
for leaks, and make necessary repairs
before starting on your trip.
Keep the rear-most windows closed.
CAUTION: (Continued)
CAUTION: (Continued)

If exhaust does come into your vehicle
through a window in the rear or
another opening, drive with your front,
main heating or cooling system on
and with the fan on any speed. This
will bring fresh, outside air into your
vehicle. Do not use the climate control
setting for maximum air because it
only recirculates the air inside your
vehicle. SeeClimate Control System
on page 230.
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself with the feel of handling and braking with
the added weight of the trailer. And always
keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as
responsive as your vehicle is by itself.
451

Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use
spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a comparative rating based
on the wear rate of the tire when tested under
controlled conditions on a specied government
test course. For example, a tire graded 150 would
wear one and a half (1.5) times as well on the
government course as a tire graded 100. The
relative performance of tires depends upon the
actual conditions of their use, however, and may
depart signicantly from the norm due to variations
in driving habits, service practices, and differences
in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C. Those grades represent the tire’s
ability to stop on wet pavement as measured under
controlled conditions on specied government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
Warning:The traction grade assigned to this
tire is based on straight-ahead braking traction
tests, and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
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