2008 GMC SIERRA panel

When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps
control to the OFF position and then release. For
vehicles rst sold in Canada, the transmission must be
in the PARK (P) position, before the DRL lamps can
be turned off.
Automatic Headlamp System
When it is dark enough outside, the automatic headlamp
system will turn on the headlamps at the normal
brightness, along with the taillamps, sidemarker, parking
lamps, and the instrument panel lights. The radio
lights will also be dim.
To turn off the automatic headlamp system, turn the
exterior lamps switch to the off position and then release
it. For vehicles rst sold in Canada, the transmission
must be in the PARK (P) position, before the automatic
headlamp system can be turned off.
The vehicle has a light sensor located on the top of the
instrument panel in the defroster grille that regulates
when the automatic headlamps turn on. Be sure it is not
covered, or the headlamps will come on whenever
the ignition is on.
The system may also turn on the headlamps when
driving through a parking garage, heavy overcast
weather, or a tunnel. This is normal.There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor detects a change in lighting lasting
longer than the delay.
If the vehicle is started in a dark garage, the automatic
headlamp system will come on immediately. Once
the vehicle leaves the garage, it takes approximately
one minute for the automatic headlamp system to
change to DRL if it is bright enough outside. During that
delay, the instrument panel cluster may not be as
bright as usual. Make sure the instrument panel
brightness control is in the full bright position. See
Instrument Panel Brightness on page 3-21.
To idle the vehicle with the automatic headlamp system
off, turn the control to the off position.
The headlamps will also stay on after you exit the
vehicle. This feature can be programmed using the
Driver Information Center (DIC). SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72.
The regular headlamp system can be turned on
when needed.
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Puddle Lamps
If your vehicle has puddle lamps, they come on when
the unlock button on the Remote Keyless Entry
(RKE) Transmitter is pressed. The lamps time out or
turn off once the engine is started.
Fog Lamps
-(Fog Lamps):If your vehicle has fog lamps, the
control is located next to the exterior lamps control
on the instrument panel, to the left of the steering
column.
The ignition must be in the ON/RUN position for the fog
lamps to come on.
Press the button to turn the fog lamps on or off. A light
will come on in the instrument panel cluster.
When the fog lamps are turned on, the parking lamps
automatically turn on.
When the headlamps are changed to high-beam, the
fog lamps also go off. When the high-beam headlamps
are turned off, the fog lamps will come on again.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied service
center to install an auxiliary roof lamp.
This button is located on
the overhead console.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the bottom of the button will
activate the lamp and illuminate an indicator light at the
bottom of this button. Pressing the top of the button
will turn off the roof mounted lamp and indicator.
The emergency roof lamp circuit is fused at 30 amps,
so the total current draw of the attached lamps
should be less than this value. The attachment points
for the roof lamp circuits are two blunt cut wires located
above the overhead console, a dark green switched
power wire and a black ground wire.
For further information on roof mount emergency lamp
installation, please visit the GM Uptter website at
www.gmuptters.com or contact your dealer.
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If your vehicle has this button, your vehicle may have
the snow plow prep package. For further information see
Adding a Snow Plow or Similar Equipment on
page 4-43.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights and
is located next to the exterior lamp control.
Push the knob to extend out and then it can be turned.
Turn the knob clockwise or counterclockwise to
brighten or dim the instrument panel lights. Turning the
knob to the farthest clockwise position turns on the
dome lamps.
Dome Lamps
The dome lamps come on when any door is opened.
They turn off after all the doors are closed.
The dome lamps can also be turned on by turning the
instrument panel brightness knob, located next to
the exterior lamps control, clockwise to the farthest
position. In this position, the dome lamps remain
on whether a door is opened or closed.
Dome Lamp Override
The dome lamp override button is located next to the
exterior lamps control.
k(Dome Off):Press the button in and the dome
lamps remain off when a door is opened. Press
the button again to return it to the extended position so
that the dome lamps come on when a door is opened.
Entry Lighting
Your vehicle has an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the dome override button is in the extended
position. If the dome override button is pressed in, the
lamps will not come on.
Exit Lighting
The interior lamps come on when the key is removed
from the ignition. They turn off automatically in
20 seconds. The lights do not come on if the dome
override button is pressed in.
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Reading Lamps
If your vehicle has reading lamps they are located on
the overhead console.
To turn on the reading lamps, press the button
located next to each lamp. To turn them off, press the
button again.
Your vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the button
located next to the lamp.
If your vehicle has a DVD Rear Seat Entertainment
(RSE) system, press the lamp lenses to turn the lamps
on or off.
The lamps are xed and cannot be adjusted.
Cargo Lamp
The cargo lamps come on by turning the instrument
panel brightness control knob to the farthest clockwise
position. This knob is located on the instrument
panel and also turns on the dome lamps.
The cargo lamp can be used if more light is needed in
the cargo area of the vehicle or in the top-box
storage units.
Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of
charge. It then adjusts the voltage for best performance
and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up
or down. This is normal. If there is a problem, an alert
will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be
spinning fast enough at idle to produce all the power
that is needed for very high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at high
speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
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Certain power accessory plugs may not be compatible
to the accessory power outlet and could result in
blown vehicle or adapter fuses. If you experience a
problem, see your dealer/retailer for additional
information on the accessory power plugs.
The accessory power outlets are powered, even when
the ignition is in LOCK/OFF. Continuing to use
power outlets while the ignition is in LOCK/OFF may
cause the vehicle’s battery to run down.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Do not use equipment
exceeding maximum amperage rating of 20
amperes. Check with your dealer/retailer before
adding electrical equipment.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment.
Notice:Improper use of the power outlet can cause
damage not covered by your warranty. Do not
hang any type of accessory or accessory bracket
from the plug because the power outlets are
designed for accessory power plugs only.Ashtray(s) and Cigarette Lighter
Your vehicle may have a front ashtray located near the
center of the instrument panel. Pull on the door to
open it. The ashtray may have a cigarette lighter.
Notice:If you put papers, pins, or other ammable
items in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage your vehicle. Never put ammable items in
the ashtray.
To remove the ashtray, open the door and pull the
ashtray bin toward you. To replace the ashtray, insert
the ashtray bin inside the ashtray door and press down
until it engages. To use the cigarette lighter, push it
in all the way, and let go. When it is ready for use, the
lighter pops back out.
Notice:Holding a cigarette lighter in while it is
heating does not let the lighter back away from the
heating element when it is hot. Damage from
overheating can occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
3-24

Climate Controls
Climate Control System (With Air
Conditioning)
With this system you can control the heating, cooling,
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.
Use the right knob to select from the following modes:
The right knob can be positioned between two modes to
select a combination of those two modes.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to the
instrument panel outlets and half to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets with some air directed to the windshield
and side window outlets. In this mode, the system
will automatically select outside air. Recirculation cannot
be selected in oor mode.
The right knob may also be used to select the defrost
and defog mode. For more information, see “Defogging
and Defrosting” later in this section.
:(Outside Air):Press this button to turn the outside
air mode on. When the button is pressed, an indicator
light will come on. When this mode is on, outside air will
circulate throughout the vehicle. The outside air mode
can be used with all modes, but it cannot be used
with the recirculation mode.
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Use the right knob to select from the following modes:
The right knob can be positioned between two modes to
select a combination of those two modes.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to the
instrument panel outlets and to the oor outlets.
6(Floor):This mode directs most of the air to the
oor outlets with some air directed to the windshield,
side window outlets, and second row oor outlets. In this
mode, the system will automatically select outside air.
Defogging and Defrosting
Fog or frost on the inside of 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.
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 someair directed to the oor vents. The system will
automatically force outside air into the vehicle.
Do not drive the vehicle until all the windows are clear.
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.
Different climate control settings can be selected for the
driver and passengers.
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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 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.
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 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.
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