light GMC SIERRA 2008 Manual PDF
[x] Cancel search | Manufacturer: GMC, Model Year: 2008, Model line: SIERRA, Model: GMC SIERRA 2008Pages: 578, PDF Size: 6.47 MB
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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.
Climate Control System
(Heater Only)
With this system you can control the heating and
ventilation for your vehicle.
Operation
9
(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob all the way counterclockwise to turn the
front system off.
Temperature Control:Turn the center knob clockwise
or counterclockwise to increase or decrease the
temperature inside the vehicle.
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Page 201 of 578

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’s side and
passenger’s 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.
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.
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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 brie y 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.
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 andC
to 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 air ow 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.
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