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Rear Window Defogger
For vehicles with a rear window defogger, a warming
grid is used to remove fog or frost from the rear window.
Be sure to clear as much snow from the rear window
as possible.
Press this button located
near the fan control to turn
the rear window defogger
on or off.
An indicator light in the button comes on when the rear
window defogger is working.
The rear window defogger will only work when the
ignition is in RUN.
The rear window defogger turns off several minutes
after the button is pressed. The defogger can also be
turned off by pressing the button again or by turning off
the engine.
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 your warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
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, 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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Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
While the engine is running, press the reset button,
located to the right of the trip odometer, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for two seconds while the
engine is running and the trip odometer is displayed,
will reset it.
To display the odometer reading with the ignition off,
press the reset button.
The hourmeter gage is accessed through the trip
odometer, for more information seeHourmeter Gage
on page 3-46.
Tachometer
This gage shows the safe operating range for the
engine speed in revolutions per minute (rpm).7.2L Caterpillar
®Diesel
Engine and Isuzu
6H Diesel EnginesGasoline and
6.6L DURAMAX®
Diesel Engines
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Airbag Readiness Light
If your vehicle has airbags, there is an airbag readiness
light on the instrument panel, which shows the airbag
symbol. The system checks the airbag’s electrical
system for malfunctions. The light tells you if there is an
electrical problem. The system check includes the
airbag sensors, the airbag modules, the wiring, the
passenger airbag suppression circuit and the crash
sensing and diagnostic module. For more information on
the airbag system, seeAirbag 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 airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.The airbag 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 airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags 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 airbag
readiness light stays on after you start your
vehicle.
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{CAUTION:
If the airbag readiness light ever comes on
when you have turned off the airbag, it means
that something may be wrong with the airbag
system. The right front passenger’s airbag
could in ate even though the switch is off.
If this ever happens, do not let anyone whom
the national government has identi ed as a
member of a passenger airbag risk group
sit in the right front passenger’s position
(for example, do not secure a rear-facing child
restraint in the right front passenger’s seat)
until you have your vehicle serviced. See
Airbag Off Switch on page 1-56andAirbag
Readiness Light on page 3-28for more on this,
including important safety information.
If the word ON or the on symbol is lit, it means that
the right front passenger’s frontal airbag is enabled
(may inflate). SeeAirbag Off Switch on page 1-56for
more on this, including important safety information.
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.
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Range Inhibit Warning Indicator
If your vehicle has an Allison 1000/2200/2300/2500 series
automatic transmission, a lighted bar under the current
gear selected will flash.
If your vehicle has an Allison 3000/3500 series
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.
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.
This light should come on briefly when you turn the
ignition key to RUN. If it does not come on, then have it
fixed so it will be ready to warn you if there is a problem.
The brake warning light may come on, and the warning
tone may sound, when you are turning and braking
at the same time. This is normal. See “Hydraulic Brake
Systems” underBraking on page 4-4.
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Parking Brake Warning Light
Your vehicle has a brake warning light. When the
ignition is on, this light will come on when you set your
parking brake. The light will stay on if your parking
brake does not release fully.
This light should also come on when you turn the
ignition key to START. If it does not come on then, have
it fixed so it will be ready to remind you if the parking
brake is applied or has not released fully.
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 is a very
important thing for you to know:
{CAUTION:
If the air brake system 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
air brake system 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.
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Anti-lock Brake System (ABS)
Warning Light
This light will come on
briefly when you start the
engine, then it will turn
off. This is normal.
If the light stays on, or comes on when you are driving,
your vehicle needs service. If the brake or low air
warning light is not on, you still have brakes, but you do
not have the antilock brake feature. If the brake
and/or low air warning light is on, you do not have
antilock brakes and there is a problem with your regular
brakes. SeeBrake System Warning Light on page 3-32
andAntilock Brake System (ABS) on page 4-5for
more information.
Trailer Antilock Brake System
Warning Light
If your vehicle is connected
to a trailer with antilock
brakes, this light should
come on briefly, as a
check, when you turn on
the ignition.
When this light comes on and stays on, it means there
is something wrong in the trailer Antilock Brake
System (ABS). Have the system repaired immediately.
If an ABS equipped trailer is not connected, this
light is not functional.
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Engine Coolant Temperature Gage
This gage shows the
engine coolant
temperature. If the gage
pointer moves into the
red area, your engine
coolant might have
overheated and your
engine may be too hot.
You should pull off the road, stop your vehicle and turn
off the engine as soon as possible.
SeeEngine Overheating on page 5-48. If you have a
Caterpillar
®diesel engine, also see your Caterpillar®
Operation & Maintenance Manual.
Low Coolant Warning Light
Your vehicle has a low
coolant warning light.
If this light comes on, the
system is low on coolant
and the engine may
overheat.
The warning light should come on briefly, as a check,
when you turn on the ignition.
When it comes on, you will also hear a warning tone for
10 seconds. SeeEngine Coolant (Caterpillar
®Diesel
Engines) on page 5-44orEngine Coolant (Gas and
DURAMAX
®/Isuzu 7.8L L6 Engines) on page 5-44
Engine Coolant and have your vehicle serviced as
soon as you can.
This light may also come on if your vehicle has the
automatic engine shutdown system and engine
shutdown has begun. SeeEngine Alarm and Automatic
Shutdown on page 2-18for more information.
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