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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 ON/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 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
inflate in a crash, or they could even inflate
without a crash. To help avoid injury, have the
vehicle serviced right away.
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Airbag Off Light
If the vehicle has an airbag on-off switch, it also has a
passenger airbag status indicator located in the
instrument panel.
When the right front
passenger airbag is
manually turned off using
the airbag on-off switch
on the instrument panel,
the indicator light OFF
will come on and stay on
to remind you that the
airbag has been turned off.
This light will go off when you turn the airbag on. See
Airbag Off Switch on page 1-55for more on this,
including important safety information.{CAUTION:
If the right front passenger’s airbag is turned off
for a person who is not in a risk group identified
by the national government, that person will not
have the extra protection of an airbag. In a crash,
the airbag will not be able to inflate and help
protect the person sitting there.
Do not turn off the passenger’s airbag unless the
person sitting there is in a risk group identified by
the national government. SeeAirbag Off Switch on
page 1-55for more on this, including important
safety information.
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{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. For example, the right
front passenger airbag could inflate even though
the airbag on-off switch is turned off.
To help avoid injury to yourself or others, have the
vehicle serviced right away. SeeAirbag Readiness
Light on page 3-27for more information, including
important safety information.
If the word ON is lit, it means that the right front
passenger frontal airbag is enabled (may inflate). See
Airbag Off Switch on page 1-55for 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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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.
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 an authorized dealer for service. If you
cannot drive to a dealer immediately, have the
vehicle towed.
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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 ON/RUN. If it does not come on, then have
it fixed so it will be ready to warn you if there is a problem.
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If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go the floor. It can take longer to stop. If the light
remains on, have the vehicle towed for service. See
Towing Your Vehicle on page 4-23for more information.
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.
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).
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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.
Antilock 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 3-31andAntilock Brake
System (ABS) on page 4-5for more information.
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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.
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.
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