light GMC SIERRA CLASSIC 2007 Repair Manual

The headlamp control has four positions:
9(Off):Turn the control to this position to turn
off the Daytime Running Lamps (DRL) and
the automatic headlamps.
AUTO (Automatic):Turn the control to this
position to activate the automatic headlamp mode.
;(Parking Lamps):Turn the control to this
position to turn on the parking lamps, together with
the following:
Sidemarker Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
Roof Marker Lamps (If the vehicle has them)
5(Headlamps):Turn the control to this position
to turn on the headlamps, together with the
previously listed lamps and lights.Switch the headlamps from high to low-beam by
pushing the turn signal/high-beam lever towards
the instrument panel.
A circuit breaker protects the headlamps. If you
have an electrical overload, the headlamps
will icker on and off. Have your headlamp wiring
checked right away if this happens.
Headlamps on Reminder
A reminder chime will sound when the headlamps
or parking lamps are manually turned on and
your ignition is off and a door is open. To disable
the chime, turn the light off.
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier
for others to see the front of your vehicle during
the day. DRL can be helpful in many different
driving conditions, but they can be especially
helpful in the short periods after dawn and before
sunset. Fully functional DRL are required on all
vehicles rst sold in Canada.
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The DRL system will come on when the following
conditions are met:
The ignition is on
The exterior lamps control is in AUTO
The light sensor determines it is daytime
When the DRL are on, only your DRL lamps will
be on. The taillamps, sidemarker, and other lamps
will not be on. The instrument panel back
lighting will not be on either.
When it begins to get dark, the automatic
headlamp system will switch from DRL to the
headlamps.
When you turn the headlamp switch off, the
headlamps will go 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 back lighting will also
be dimly lit.
To turn off the automatic headlamp system, turn
the exterior lamps switch to the off position.
Turning off the automatic headlamp system with
the headlamp switch is not available for vehicles
rst sold in Canada.
Your 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.
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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 you start your vehicle in a dark garage, the
automatic headlamp system will come on
immediately. Once you leave the garage, it will
take approximately one minute for the automatic
headlamp system to change to DRL if it is
bright enough outside. During that delay, your
instrument panel cluster may not be as bright as
usual. Make sure your instrument panel brightness
control is in the full bright position. SeeInstrument
Panel Brightness on page 226.To idle your vehicle with the automatic headlamp
system off, turn the control to the off position.
You may be able to turn off your Automatic
Headlamp System. SeeDaytime Running Lamps
(DRL) on page 222for more information.
Your headlamps will also stay on after you exit the
vehicle. You can program this feature using the
Driver Information Center (DIC). SeeDIC Vehicle
Customization on page 282.
As with any vehicle, you should turn on the
regular headlamp system when needed.
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Fog Lamps
If your vehicle has fog lamps, use them for better
vision in foggy or misty conditions.
The fog lamp button is
located on the left side
of the instrument
panel.
The parking lamps and/or low-beam headlamps
must be on for the fog lamps to work.
Press the button to turn the fog lamps on or off.
An indicator light will glow in the button when
the fog lamps are on.Remember, fog lamps alone will not give off as
much light as the headlamps. Never use the
fog lamps in the dark without turning on the
headlamps.
The fog lamps will go off whenever the high-beam
headlamps come on. When the high beams go
off, the fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps
after you restart the vehicle, you will need to press
the fog lamp button again.
Some localities have laws that require the
headlamps to be on along with the fog lamps.
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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 center of the
instrument panel near
the climate controls.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate
the lamp and illuminate an indicator light near the
button. Pressing the button again will turn off
the roof mounted lamp.
If your vehicle has this button, your vehicle may
have the snow plow prep package. For further
information seeAdding a Snow Plow or Similar
Equipment on page 416.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel
lights.
The thumbwheel for this feature is located next to
the headlamp control.
Move the thumbwheel up to adjust the instrument
panel lights and to return the radio display to
full brightness when the headlamps or parking
lamps are on. To turn on the dome lamps, move
the thumbwheel to the farthest position.
Dome Lamps
The dome lamps come on when a door is opened.
The dome lamps can be turned on by moving
the thumbwheel, located next to the exterior lamps
control, to the farthest position. In this position,
the dome lamps will remain on whether a door is
opened or closed.
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Dome Lamp Override
E(Dome Lamp Override):You can use the
dome override button, located below the exterior
lamps control, to set the dome lamps to come
on automatically when a door is opened, or
to remain off. To turn the lamps off, press the
button in. With the button in this position, the dome
lamps will remain off when the doors are open.
To return the lamps to automatic operation, press
the button again to return it to the extended
position. With the button in this position, the dome
lamps will come on when you open a door.
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
With exit lighting, the interior lamps will come on
when the key is removed from the ignition.
They will turn off automatically in 20 seconds. The
lights will not come on if the dome override
button is pressed in.
Front Reading Lamps
The reading lamps are located on the overhead
console.
To turn the reading lamps on or off, press the
button located next to each lamp.
The lamps can be adjusted to a desired direction.
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. These
lamps are xed and cannot be adjusted.
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Cargo Lamp
The cargo lamp button
is located on the left
side of the instrument
panel. Press the
button to turn the cargo
lamp on or off.
An indicator light on the instrument panel cluster
will come on when the cargo lamp is turned
on, and the ignition key is turned to RUN.
Accessory Power Outlet(s)
Accessory power outlets can be used to connect
auxiliary electrical equipment, such as a cellular
telephone or CB radio. The outlet can accept
electrical equipment up to a maximum of
20 amperes.
Your vehicle may have two accessory power
outlets, or may have one accessory power outlet
located near the cigarette lighter, if the vehicle
has one. The cigarette lighter is designed to t only
in the receptacle to the right of the accessory
power outlet.
To use an outlet, remove the protective cap.
When not in use, always cover the outlet with the
protective cap. The accessory power outlet is
operational at all times.
Notice:If electrical devices are left plugged
into a power outlet, the battery may drain
causing your vehicle not to start or damage to
the battery. This would not be covered by
the warranty. Always unplug all electrical
devices when turning off your vehicle.
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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 for
additional information on the accessory power
plugs.
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 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.
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 front ashtray, pull the ashtray
toward you. To replace the ashtray, place
the ashtray on the slides at the side of its location
in the instrument panel. To use the cigarette
lighter, push it in all the way, and let go. When it
is ready, the lighter will pop back out by itself.
Notice:Holding a cigarette lighter in while it
is heating will not allow the lighter to back
away from the heating element when it is hot.
Damage from overheating may occur to the
lighter or heating element, or a fuse could be
blown. Do not hold a cigarette lighter in
while it is heating.
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Mode Control
To change the current mode, select one of the
following:
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; then directs most
of the remaining air to the oor outlets. A little air
is directed toward the windshield and the side
window outlets. Cooler air is directed to the upper
outlets and warmer air to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets with a little air directed to the
windshield and the side window outlets.
h(Recirculation):The recirculation mode is
used to recirculate the air inside of your vehicle.
Use this mode to help prevent outside odors
and/or dust from entering your vehicle or to help
cool the air inside of your vehicle more quickly.
Press this button to turn the recirculation mode on
or off. The light on the recirculation button will
illuminate. Recirculation cannot be used in oor,
defog or defrost modes. An indicator on the button
will light up, ash three times and turn off when
recirculation is selected in these modes. The
air-conditioning compressor will also come 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 fan speed.
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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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