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This switchbank is located in the center of the
instrument panel.
e(Marker Lamp Defeat Switch):SeeMarker
Lamps on page 152.
j(Manual High Idle Switch):SeeHigh Idle
System on page 106.
i(Traction Control Switch):SeeTraction
Control System (TCS) on page 216.
f(Outside Heated Mirror Switch):SeeOutside
Heated Mirrors on page 134.
g(Power Take Off Switch):SeePower
Take-Off (PTO) on page 118.
h(Rear Air Suspension Dump Control
Switch):Air Suspension on page 129.
k(Rear Axle Shift Control Switch):SeeAir Shift
Control (Automatic Transmission) on page 114.
q(Exhaust Brake Switch):SeeDiesel Engine
Exhaust Brake on page 112.
l(Differential Lock Control Switch):See
Rear Axle Differential Lock Control on page 215.
c(Airbag On/Off Switch):SeeAirbag Off
Switch on page 76.
If your vehicle does not have some of the features
controlled by these switches, there will be a
blank switch marker in its place.
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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.
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 system
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.
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The brake system 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” under
Braking on page 210.
This light is located
above the climate
controls in the center of
the instrument panel.
If the service brakes soon warning light comes on,
it means there may be something wrong in the
brake system.
When this light comes on, you will also hear a
warning tone. Have the system repaired
immediately.Both of these lights should come on briefly every
time you start your engine. If they do not come
on then, have them fixed so they will be ready to
warn you if there is 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 this light is still on, have the
vehicle towed for service. SeeTowing Your
Vehicle on page 241. See “Hydraulic Brake
Systems” underBraking on page 210for further
information.
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Parking Brake Warning Light
This light will also come on when you set the
parking brake. The light will stay on if your parking
brake does not release 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’s
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.
United StatesCanada
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Anti-Lock Brake System
Warning Light
This light will come on
briefly when you start
your 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 anti-lock
brake feature. If the BRAKE and/or LOW AIR
warning light is on, you do not have anti-lock
brakes and there is a problem with your regular
brakes. SeeBrake System Warning Light on
page 169andAnti-Lock Brake System (ABS) on
page 212for more information.
The anti-lock brake system warning light should
come on briefly when you turn the ignition
key to ON. If the light does not come on then,
have it fixed so it will be ready to warn you if
there is a problem.
Trailer Anti-Lock Brake System
Warning Light
This light is located
above the climate
controls in the center of
the instrument panel.
If your vehicle is connected to a trailer with
anti-lock 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 anti-lock
brake system. Have the system repaired
immediately.
If an anti-lock brake system equipped trailer is not
connected, this light is not functional.
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Transmission Temperature Gage
If you have an automatic
transmission and this
gage, it is located above
the switchbank in the
center of the instrument
panel.
When your ignition is on, the gage shows the
temperature of the transmission oil. A reading in
the warning zone, the red area beginning at 300°F
(150°C), means you must stop driving and
check into the cause. One possible cause is a low
oil level in the transmission.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the
transmission. This could lead to costly repairs
that would not be covered by your warranty.
Do not drive your vehicle while the
transmission temperature gage reading is
above normal. See your dealer for service.
Exhaust Brake Indicator Light
If your vehicle is
equipped with an
exhaust brake, you will
have this light, located
above the climate
controls in the center of
the instrument panel.
The exhaust brake indicator light will come on and
stay on whenever the diesel engine exhaust brake
or exhaust restrictor is active. For more information,
seeDiesel Engine Exhaust Brake on page 112and
Exhaust Restrictor (Engine Warm-Up) on page 108.
Differential Lock Indicator Light
If your vehicle has this
feature, this light is
located in the center of
the instrument panel.
The light is on when the
rear differential lock
system is in use.
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Air Pressure Gage
If your vehicle has air
brakes, the air pressure
gage is located above
the switchbank in
the center of the
instrument panel.
This gage shows the air pressure for both your
front and rear brake systems.
If the needle on the gage indicates that the air
pressure is below 60 to 75 psi (415 to 517 kPa),
the low air warning light will come on. An alarm will
also sound if this happens.The top pointer shows the pressure available for the
front system, while the bottom pointer shows
pressure for the rear. There should be no more than
4 psi (28 kPa) difference showing between the
systems.
Don’t drive until both pointers are showing at least
120 psi (827 kPa), so you’ll have enough air if
you need to apply your brakes.
Hourmeter Gage
To access the engine hourmeter gage, press the
trip odometer button three times.
The instrument panel cluster displays the
accumulated engine run time hours using the
reconfigurable odometer display. The engine run
time hours displays only when the ignition is in the
LOCK or ACCESSORY position and the trip
reset button is pressed for about four seconds.
The value of the accumulated hours does
not change when the battery is disconnected.
The hourmeter resets to 0.0 when 10,000 hours
are accumulated. The instrument panel cluster
begins to reaccumulate the engine run time hours
from 0.0 hours.
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While your vehicle is parked:
•Familiarize yourself with all of its controls.
•Familiarize yourself with its operation.
•Set up your audio system by presetting your
favorite radio stations, setting the tone, and
adjusting the speakers. Then, when driving
conditions permit, you can tune to your favorite
radio stations using the presets and steering
wheel controls if the vehicle has them.
Notice:Before adding any sound equipment to
your vehicle, such as an audio system, CD
player, CB radio, mobile telephone, or two-way
radio, make sure that it can be added by
checking with your dealer. Also, check federal
rules covering mobile radio and telephone
units. If sound equipment can be added, it is
very important to do it properly. Added sound
equipment may interfere with the operation of
your vehicle’s engine, radio, or other systems,
and even damage them. Your vehicle’s systems
may interfere with the operation of sound
equipment that has been added.Notice:The chime signals related to safety
belts, parking brake, and other functions
of your vehicle operate through the
radio/entertainment system. If that equipment
is replaced or additional equipment is added
to your vehicle, the chimes may not work. Make
sure that replacement or additional equipment
is compatible with your vehicle before
installing it.
Setting the Time
Press and hold the HR (down) or MIN (up) arrow
for two seconds. Then press HR until the
correct hour appears on the display. Press and
hold MIN until the correct minute appears on
the display. The time can be set with the ignition
on or off.
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