light CHEVROLET TRAIL BLAZER 2009 1.G Service Manual

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 bring the charge back up. 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 are on, such as: 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.
EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increase engineidle speed to generate more power, whenever needed.
It can temporarily reduce the power demands of some
accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as BATTERY SAVER ACTIVE,
BATTERY VOLTAGE LOW, or LOW BATTERY. If this
message is displayed, it is recommended that the driver
reduce the electrical loads as much as possible. SeeDIC
Warnings and Messages on page 3-51.
Battery Run-Down Protection
This feature shuts off the dome, courtesy, and vanity
lamps if they are left on for more than 20 minutes when
the ignition is off. This helps to keep the battery from
running down.
If the battery run-down protection shuts off the interior
lamps, it may be necessary to do one of the following to
return to normal operation:
Shut off all lamps and close all doors.
Turn the ignition key to ON/RUN.
This feature also turns off the parking lamps and
headlamps under most circumstances, if they are left
on. Turn the exterior lamps knob to turn them back on.
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Accessory Power Outlet(s)
Accessory power outlets let you plug in auxiliary
electrical equipment, such as a cellular telephone.
The vehicle has three accessory power outlets.
There are two outlets located below the climate
controls and one outlet is on the rear of the center
oor console.
Remove the cover from the outlet to use the outlet.
Be sure to put the cover back on when not using the
accessory power outlet.
Certain electrical accessories may not be compatible
with the accessory power outlet and could result
in blown vehicle or adaptor fuses. If you experience
a problem, see your dealer/retailer for additional
information on the accessory power outlets.
Notice:Adding any electrical equipment to the
vehicle can damage it or keep other components
from working as they should. The repairs would
not be covered by the vehicle 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 the 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
For vehicles with 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 the 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.
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6(Floor):Air is directed to the oor outlets, with
some air directed to the windshield and the side window
outlets. The recirculation button cannot be selected
while in oor mode.
-(Defog):This mode clears the windows of fog or
moisture. Air is directed to the oor, windshield and
side window outlets. The recirculation button cannot
be selected while in defog mode.
1(Defrost):This mode clears the windows of fog or
frost more quickly. Air is directed to the windshield and
the side window outlets, with some 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.
#(Air Conditioning):Press to turn the
air-conditioning system on or off. An indicator light
comes on and the system begins 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.
@(Recirculation):Press to turn the recirculation
mode on. An indicator light comes to show that the
recirculation is on. This mode recirculates and helps to
quickly cool the air inside the vehicle. It can be used to
help prevent outside air and odors from entering the
vehicle. 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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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear):Press to turn the rear window defogger
on or off. An indicator light in the button comes on to
show that the rear window defogger is on. The rear
window defogger automatically turns off approximately
ten minutes after the button is pressed.
For vehicles with heated mirrors, they turn on when the
rear window defogger button is pressed.
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.
Dual Automatic Climate Control
System
With this system the heating, cooling and ventilation
can be controlled on the vehicle. When the vehicle is
rst started and the climate control system is on, or if the
climate control system has been turned on, the display
shows the driver’s temperature setting for ve seconds.
Then it shows the outside temperature.
A. Driver and Passenger
Side Temperature
Controls
B. Fan Control
C. Display
D. AUTO
E. Power ButtonF. Recirculation
G. Air Conditioning
H. Defrost
I. Air Delivery Mode
Control
J. Rear Window
Defogger
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#A/C (Air Conditioning):Press to turn the air
conditioning system on or off. When the system is on,
the system automatically begins to cool and dehumidify
the air inside of the vehicle. The air conditioning symbol
appears on the display when the air conditioning is on
and turns off when the air conditioning is off.
If the air conditioning is turned off while in front defrost
or defog mode, the air conditioning symbol turns off,
however, the A/C compressor remains 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.@(Recirculation):Press to turn the recirculation
mode on or off. An indicator light comes on to show
that recirculation is on. This mode recirculates and
helps to quickly cool the air inside the vehicle. It can
be used to help prevent outside air and odors from
entering the vehicle. Recirculation mode can be used
with vent and bi-level modes, but it cannot be used
with oor, defog or defrost modes.
If recirculation mode is selected with oor, defog,
or defrost modes, the indicator ashes three times
and turns off to indicate the selection is not available.
The air conditioning compressor may also run while
in recirculation mode. This is normal and helps to
prevent window 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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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear):Press to turn the rear window defogger on
or off.
An indicator light comes on to show that the rear
window defogger is on.
The rear window defogger will turn off approximately
10 minutes after the button is pressed. If additional
warming time is needed, press the button again.
The heated mirrors will also come on when the rear
window defogger is turned on. SeeOutside Heated
Mirrors on page 2-44.
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 the vehicle.
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If the vehicle has the rear seat audio system, the lower
buttons are used to adjust the rear seat climate control
system. The temperature of the air coming through the
rear outlets is determined by the front passenger
temperature setting.
P(On/Off):Press to turn the rear climate controls on
or off.
z9y(Fan Control):Press to increase or decrease
the fan speed.
z\y(Air Delivery Mode Control):Press to
change the direction of airow (panel, bi-level or oor)
to the rear seat area.
The rear control only turns on if the front climate control
system is on and not in defrost mode.
Warning Lights, Gages, and
Indicators
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
the warning lights and gages could prevent injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. Some
warning lights come on briey when the engine is
started to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
may be a problem, check the section that explains
what to do. Follow this manual’s advice. Waiting to
do repairs can be costly and even dangerous.
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Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime sounds for several
seconds to remind a driver to fasten the safety belt,
unless the driver safety belt is already buckled.
The safety belt light comes
on and stays on for several
seconds, then ashes for
several more.
This chime and light are repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s
safety belt is already buckled, neither the chime nor
the light comes on.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a
chime sounds for several seconds to remind the front
passenger to buckle their safety belt. This only occurs
if the passenger airbag is enabled. SeePassenger
Sensing System on page 1-63for more information.
The passenger safety belt light, located on the instrument
panel, comes on and stays on for several seconds and
then ashes for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger safety belt is buckled, neither the
chime nor the light comes on.
The front passenger safety belt warning light and
chime may turn on if an object is put on the seat such
as a briefcase, handbag, grocery bag, laptop or other
electronic device. To turn off the warning light and or
chime, remove the object from the seat or buckle the
safety belt
3-31

Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check includes
the airbag sensor, the pretensioners, the airbag modules,
the wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-55.
The airbag readiness light
ashes for a few seconds
when the engine is started.
If the light does not come
on then, have it xed
immediately.{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving,
it means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have
the vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-51
for more information.
3-32

Passenger Airbag Status Indicator
The vehicle has the passenger sensing system.
SeePassenger Sensing System on page 1-63for
important safety information. The rearview mirror
has a passenger airbag status indicator.When the vehicle is started, the passenger airbag status
indicator will light ON and OFF, or the symbol for on and
off, for several seconds as a system check. Then, after
several more seconds, the status indicator will light either
ON or OFF, or either the on or off symbol to let you know
the status of the right front passenger frontal airbag.
If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger frontal airbag is enabled (may inate).
If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger
frontal airbag.
United States
Canada
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