light CHEVROLET TRAIL BLAZER 2008 1.G Service Manual

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 are only affected when the
light sensor sees a change in lighting lasting longer
than the delay.
If you start your vehicle in a dark garage, the automatic
headlamp system comes on after the transmission is
shifted out of PARK (P). Once you leave the garage, it
will take about one minute for the automatic headlamp
system to change to DRL if it is light outside. During that
delay, the instrument panel cluster might not be as
bright as usual. Make sure the instrument panel
brightness control is in the full bright position.
If the vehicle is running and the automatic headlamp
system is already on, it can be turned off by turning and
releasing the headlamp control at the off position.
The automatic headlamp system stays off until you turn
and release the headlamp control at the off position
again. SeeHeadlamps on page 3-14.Fog Lamps
Your vehicle may have this feature. Use your fog lamps
for better vision in foggy or misty conditions. Your
ignition must be in RUN for your fog lamps to work.
The fog lamp button is
located on the instrument
panel to the right of
the exterior lamps knob.
Press the button to turn the fog lamps on. Press the
button again to turn them off. A light will glow near the
button while the fog lamps are on. Fog lamps will
turn off whenever your high-beam headlamps are on.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
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Instrument Panel Brightness
Press the knob located
next to the exterior lamps
knob to extend it.
Turn the knob to adjust the instrument panel lights.
Turn the knob all the way up to turn on the
interior lamps. Press the knob back into its stored
position when you are not using it.
Dome Lamps
The dome lamps will come on when you open a door
unless the dome lamp override is pressed in.
Dome Lamp Override
The dome override button
is located below the
exterior lamps knob.
To turn the dome lamps off, press the button. The dome
lamps will remain off when a door is open. This will
override the illuminated entry feature unless you use the
Remote Keyless Entry (RKE) transmitter to unlock the
vehicle.
To return the lamps to automatic operation, press the
button again. The dome lamps come on when a door
is opened.
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Entry Lighting
The vehicle has entry lighting.
When any door is opened, the dome lamps come on as
long as the dome override lamp override button is
not pressed in. When all the doors are closed, the lamps
stay on for a short period of time and then turn off
automatically. If you use the Remote Keyless Entry
(RKE) transmitter to unlock the vehicle, the interior
lamps come on for a short time whether or not the
dome lamp override is on.
Exit Lighting
With exit lighting, the interior lamps come on when you
remove the key from the ignition. If the dome override
is off, these lamps stay on for a short period of time and
then go out.
Reading Lamps
The reading lamps are located in the front console.
Press the lens on the lamps to turn the reading lamps
on or off.
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.
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Ashtray(s) and Cigarette Lighter
Your vehicle may have this feature. The ashtray is
removable and ts into the front cupholder.
Notice:If papers, pins, or other ammable items
are put 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, pull the covered bin out of the
cupholder.
To use the lighter, press it in all the way, and let go.
When it is ready, it 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. Do not use
equipment exceeding maximum amperage rating
of 20 amperes.
Climate Controls
Dual Climate Control System
With this system you can control the heating, cooling,
and ventilation for your vehicle.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
If the knob is in off mode, outside air still enters the
vehicle, and is directed based on the position of
the mode knob. The temperature can still be adjusted
using the temperature knob.
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Turn the right knob clockwise or counterclockwise to
direct the airow inside of your vehicle.
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 about 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 vents
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. The recirculation button
cannot be selected while in oor mode.
@(Recirculation):Recirculation mode is used to
recirculate the air inside of your vehicle. When this button
is pressed, an indicator light in the button will come on to
let you know that it is active. 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. 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.Defog and defrost modes are described later in this
section.
Driver’s Side Temperature Lever: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.
Slide the lever up or down to adjust the temperature.
Passenger’s Side Temperature Lever: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. Slide the lever up or down to adjust
the temperature. This lever also adjusts the temperature
to the rear seat outlets.
When the temperature outside is 0°F (-18°C) or lower,
use the engine coolant heater, if the vehicle has one,
to provide warmer air, faster to your 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 the vehicle. You may notice a slight change in engine
performance when the air conditioning compressor
shuts off and turns on again. This is normal.
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Defogging and Defrosting
Fog 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. 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 clockwise or counterclockwise to
select one of the following modes:
-(Defog):This mode directs the air to the oor outlets,
windshield and side window outlets. The recirculation
button cannot be selected while in defog mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window outlets, with only a little
air directed to the oor outlets. The air conditioning
compressor may run to dehumidify the air to prevent
window fogging. The recirculation button cannot be
selected while in defrost mode. Do not drive the vehicle
until all the windows are clear.
Rear Window Defogger
If your vehicle has the rear window defogger a warming
grid is used to remove fog on the rear window.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light in the button
will come on to let you know that the rear window
defogger is active. The rear window defogger will
automatically turn off approximately ten minutes after
the button is pressed.
If your vehicle has heated mirrors, this button will
activate them.
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 the vehicle warranty. Do not attach
a temporary vehicle license, tape, a decal or
anything similar to the defogger grid.
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Manual Operation
To change the current setting, select one of the
following:
w9x(Fan):This button allows you to manually adjust
the fan speed. Press the up arrow to increase fan speed
and the down arrow to decrease fan speed. The display
will change to show you the selected fan speed and the
driver’s side temperature setting for ve seconds.
C(Mode):Press this button to manually change the
direction of the airow in your vehicle. Keep pressing the
button until the desired mode appears on the display.
The display will change to show you the selected
air delivery mode and the driver’s temperature setting
for ve seconds.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs approximately half of
the air to the instrument panel outlets, then directs
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. Some air also comes out of the defroster
and side window outlets. The recirculation button
cannot be selected in oor mode.
@(Recirculation):Press this button to turn
recirculation mode on or off. When this button is
pressed, an indicator light in the button will also come
on to let you know that it is activated. 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. Recirculation
mode can be used with vent and bi-level modes, but it
cannot be used with oor, defog or defrost modes.
Defog and defrost modes are described later in
this section.
If recirculation mode is selected with oor, defog, or
defrost modes, the indicator will ash three times and
then turn off indicating the selection is not available.
You may also notice that the air conditioning compressor
will run while in recirculation mode. This is normal
and will help to prevent fogging.
If the weather is cold and damp, the system may cause
the windows to fog while using recirculation mode.
If the windows do start to fog, select defog or defrost
mode and increase fan speed.
Recirculation mode, if selected, will be cleared when the
engine is turned off.
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#A/C (Air Conditioning):Press this button to
manually turn the air conditioning system on or off.
When the system is on, the system will automatically
begin to cool and dehumidify the air inside of your
vehicle. The air conditioning symbol will appear on the
display when the air conditioning is on and will turn
off when the air conditioning is off.
If you turn the air conditioning off while in front defrost
or defog mode, the air conditioning symbol will turn
off, however, the A/C compressor will remain on to help
de-humidify the air inside the vehicle. If one of the
other modes is selected the compressor will then turn
the A/C off until it is selected again or the AUTO button
is pressed.
To avoid fogging the inside glass on rainy and humid
days at a temperature above freezing, press the
air conditioning button to run the A/C compressor.
Also it is best to avoid the use of the recirculation mode
except when maximum air conditioning performance
is needed or for short times to avoid exterior odors.
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 moisture
condensing on the cool window glass. This can be
reduced if the climate control system is used properly.
You can use either defog or front defrost to clear
fog or frost from your windshield.
-(Defog):Use this setting to clear the windows of
fog or moisture. This setting will deliver air to the
oor and windshield outlets.
0(Front Defrost):Press the front defrost button to
clear the windshield and side windows of frost or
fog quickly. 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. Do not drive
the vehicle until all the windows are clear.
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Rear Window Defogger
If your vehicle has the rear window defogger a warming
grid is used to remove fog from the rear window.
<(Rear):Press this button to turn the rear window
defogger on or off.
An indicator light in the button will come on to let you
know that the rear window defogger is activated.
The rear window defogger will turn off approximately
10 minutes after the button is pressed. If you need
additional warming time, press the button again.
If your vehicle has heated mirrors, they will come on
when this button is pressed.
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.
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.
Rear Climate Control System
Your vehicle has one of the following rear climate
control systems. With either of these systems, the rear
climate controls will be disabled when the front
climate control system is in defrost. This occurs to
provide maximum airow to clear the windshield.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
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
your 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 you
will see in the details on the next few pages, some
warning lights come on briey when you start the engine
just to let you know they’re 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’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when 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 warning lights
and gages. They’re a big help.
Your vehicle may also have a Driver Information Center
(DIC) that works along with the warning lights and
gages. SeeDriver Information Center (DIC) on
page 3-49.
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