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If your vehicle has air conditioning, the controls will look
like this:
On hot days, open the windows to let hot inside air
escape; then close them. This helps to reduce the time
it takes for your vehicle to cool down. It also helps
the system to operate more efficiently.
<(Maximum Air Conditioning):Turn the right knob
to this setting for maximum cooling. This setting puts
the system in recirculation mode and helps to maximize
your air conditioner’s performance and your vehicle’s
fuel economy. This setting also cools the air the fastest.
Y(Air Conditioning):This setting is used for normal
cooling on hot days. It cools outside air and directs
it through the instrument panel vents.
)(Bi-Level Air Conditioning):This setting divides
airflow between the floor vents and instrument panel
vents. The air conditioning compressor will cycle
continuously in this setting as long as the outside
temperature is warm enough to activate the compressor.
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 is used properly.
There are two modes to clear fog or frost from your
windshield and side windows.
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. For best results, clear all snow and ice from the
windshield before defrosting.
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Outlet Adjustment
Your vehicle has air outlets
on the instrument panel
that allow you to adjust the
direction and amount of
airflow inside the vehicle.
Move the lever on the outlet up or down to direct the
airflow. Increase or reduce the amount of airflow
by opening and closing the louvers. The outlets can be
moved side-to-side to direct the airflow.
Operation Tips
•
Keep the hood and front air inlets free of ice, snow,
or any other obstruction (such as leaves). The
heater and defroster will work far better, reducing
the chance of fogging the inside of your windows.
•Keep the air path under the front seats clear
of objects. This helps air to circulate throughout
your vehicle.
•Adding outside equipment to the front of your
vehicle, such as hood-air deflectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
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Instrument Panel Cluster
Your instrument panel cluster is designed to let you know at a glance how your vehicle is running. You’ll know how
fast your going, about how much fuel is left and many other things you’ll need to drive safely and economically.
United States Diesel Engine shown, Canada and Gasoline Engine similar
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Air Bag Readiness Light
If your vehicle has air bags, there is an air bag readiness
light on the instrument panel, which shows the airbag
symbol. The system checks the air bag’s electrical
system for malfunctions. The light tells you if there is an
electrical problem. The system check includes the air
bag sensors, the air bag modules, the wiring, the
passenger air bag suppression circuit and the crash
sensing and diagnostic module. For more information on
the air bag system, seeAir Bag System on page 1-48.
This light will come on
when you start your
vehicle, and it will flash for
a few seconds. Then
the light should go out.
This means the system
is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN or
START. If the light doesn’t come on then, have it fixed
so it will be ready to warn you if there is a problem.
{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not in ate in a crash, or they
could even in ate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the air bag
readiness light stays on after you start
your vehicle.
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Charging System Light
The charging system light
may be located in the
instrument panel cluster, or
with the auxiliary warning
lights in the center of
the instrument panel.
It should come on briefly when you turn on the ignition,
before the engine is running, as a check to show
that it is working.
If it stays on, or comes on while you are driving, have
your vehicle checked right away. You could have a loose
generator drive belt or some other problem.
Driving while this light is on will drain your battery. If you
must drive a short distance with the light on, turn off
your radio and other accessories. Sustained driving with
a generator failure could result in a lack of back-up
braking if the engine quits or the power steering pump
should fail.
Voltmeter Gage
When your engine is
running, the voltmeter
gage shows the charging
system voltage.
Readings in either warning zone indicate a possible
problem in the electrical system.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system may not be able to provide full power
at engine idle. As engine speeds are increased,
this condition should correct itself because higher
engine speeds allow the charging system to create
maximum power.
You can only drive a short time on the battery. Be sure
to shut off the radio, the fan or any unnecessary
accessories and have the system serviced.
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Service Transmission Warning Light
If your vehicle has an Allison automatic transmission,
certain transmission malfunctions will turn this light on.
This light is located with
the auxiliary warning lights
in the center of the
instrument panel.
If this light comes on while you are driving, do not use
the transmission shift control or you may lose forward
gears. The computer for the transmission senses
a problem and chooses a gear to stay in so that you
can drive the vehicle in that gear. You may not be able
to drive as fast or back up when this light is on.
Notice:If you continue driving your vehicle after
the transmission warning light comes on, you could
damage the transmission. While this light is on,
the transmission cannot operate in all gears. If you
attempt to shift gears, the vehicle may not
continue to move. Do not attempt to shift gears
while the transmission warning light is on. Instead,
drive directly to a GM dealer for service. If you
cannot drive to a dealer immediately, have the
vehicle towed.
Range Inhibit Warning Indicator
If your vehicle has an Allison
1000/2000/2200/2400 series automatic transmission, a
lighted bar under the current gear selected will flash.
If your vehicle has an Allison MD automatic
transmission, the current gear selected on the
pushbutton display will flash.
The flashing bar or gear selection indicates that
transmission range shifts may not occur.
For detailed information on shift inhibit limitations, see
the Allison Automatic Transmission Operator’s Manual in
your vehicle for further information.
Brake System Warning Light
Your vehicle has either hydraulic or air brakes. Each
system has different warning lights.
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Hydraulic Brake System
Warning Lights
Vehicles with hydraulic brake systems have two brake
system warning lights on the instrument panel.
If the BRAKE warning light
comes on, it means that
the fluid level in the master
cylinder reservoir is low
or there is another problem
with your hydraulic
brakes.
When it comes on, you will also hear a warning tone.
The BRAKE warning light may come on, and the
warning tone may sound, when you’re turning and
braking at the same time. This is normal. SeeHydraulic
Brake SystemsunderBraking on page 4-6.If the service brakes soon
warning light comes on, it
means there is something
wrong in the brake
system.
When this light comes on, you will also hear a warning
tone. If this light comes on, have the system repaired
immediately.
Both of these lights should come on briefly every time
you start your engine. If they don’t come on then,
have them fixed so they will be ready to warn you if
there’s a problem. If one or both of these warning lights
stay on after you start the engine, there could be a
brake problem. Have your brake system inspected
right away.
If one or both of these lights come on while you are
driving, pull off the road and stop carefully. You
may notice that the pedal is harder to push. Or, the
pedal may go closer to the floor. It may take longer to
stop. If the BRAKE light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-31. SeeHydraulic Brake SystemsunderBraking
on page 4-6for further information.
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Air Brake System Warning Light
Vehicles with air brake systems have a brake system
warning light on the instrument panel.
The LOW AIR warning light should come on, as a
check, whenever you start the engine. However, it is
designed to come on, and stay on, when brake reservoir
pressure has dropped below 60 psi (410 kPa).
When the warning light comes on while you are driving,
you should drive only as far as the nearest point of
safety and then stop the vehicle. Here’s a very important
thing for you to know:{CAUTION:
If the LOW AIR warning light comes on and the
warning tone sounds, the vehicle can stop
suddenly and without further warning. This is
because the parking brake will come on if
the pressure falls below 35 to 45 psi (240 to
310 kPa). You or others could be injured. If the
LOW AIR warning light comes on and the
warning tone sounds, stop as soon as you
can. You will not know how quickly the system
is losing pressure, so be aware that the
parking brake may come on suddenly. United States
Canada
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