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Low Washer Fluid Warning Light.....................3-42
Check Gages Warning Light...........................3-42
Fuel Gage...................................................3-42
Water in Fuel Warning Light...........................3-43
Air Filter Restriction Indicator..........................3-44
Air Pressure Gage........................................3-44
Hourmeter Gage...........................................3-45
Audio System(s).............................................3-45
Setting the Time...........................................3-45
AM-FM Radio...............................................3-46Radio with Cassette......................................3-48
Radio with CD..............................................3-53
Theft-Deterrent Feature (Non-RDS Radios).......3-57
Radio Reception...........................................3-57
Care of Your Cassette Tape Player.................3-57
Care of Your CDs.........................................3-59
Care of Your CD Player................................3-59
Fixed Mast Antenna......................................3-59
Chime Level Adjustment................................3-59
Section 3 Instrument Panel
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A. Air Outlets. SeeOutlet Adjustment on page 3-22.
B. Instrument Panel Cluster. SeeInstrument Panel
Cluster on page 3-24.
C. Shift Lever. SeeStarting Your Gasoline Engine on
page 2-12,Starting Your Diesel Engine on page 2-14
andStarting Your DURAMAX™ Diesel Engine on
page 2-19.
D. Air Brake Controls. See ‘‘Air Brake’’ underParking
on page 2-33.
E. Auxiliary Gages. SeeWarning Lights, Gages, and
Indicators on page 3-23.
F. Exterior Lamp Control. SeeExterior Lamps on
page 3-13.
G. Turn Signal/Multifunction Lever. SeeTurn
Signal/Multifunction Lever on page 3-7.
H. Hazard Warning Flashers Button. SeeHazard
Warning Flashers on page 3-5.
I. Audio System(s). SeeAudio System(s) on
page 3-45.
J. Climate Controls. SeeClimate Control System on
page 3-19.
K. Instrument Panel Switchbank. SeeInstrument Panel
Switchbank on page 3-16.
L. Air Bag Off Switch. SeeAir Bag Off Switch on
page 1-55.
M. Accessory Power Outlets. SeeAccessory Power
Outlets on page 3-17.Hazard Warning Flashers
Your hazard warning flashers let you warn others. They
also let police know you have a problem. Your front
and rear turn signal lamps will flash on and off.
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Your hazard warning
flashers button is located
on top of the steering
column.
Your hazard warning flashers work no matter what
position your key is in, and even if the key isn’t in.
Press the button to make the front and rear turn signal
lamps flash on and off. Press the button again to
turn the flashers off.
When the hazard warning flashers are on, your turn
signals won’t work. The hazard warning flashers will not
flash if the brakes are applied.Other Warning Devices
If you carry reflective triangles, you can set one up at
the side of the road behind your vehicle in the
recommended manner per Federal Motor Carrier Safety
Regulation (FMCSR) Section 392.22, to warn others.
Horn
Sound the horn by pushing the center of the steering
wheel. If you have the optional air horn, it is controlled
by a cord that you’ll find up above and to the left of
the driver. The harder you pull on the cord, the louder
the air horn will sound. The air horn works only after
your air brake system pressure gets up to about
115 psi (790 kPa). The air horn will work properly
unless the the air brake system pressure drops below
60 psi (415 kPa).
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Rear Heating System
If your vehicle has a rear
heater, the thumbwheel for
this feature is located on
the headliner.
To increase and decrease the flow of heated air to
the rear floor vents, turn the thumbwheel to the
desired fan speed. To turn the fan off, turn the
thumbwheel down.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.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
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly – and even
dangerous. So please get to know your warning lights
and gages. They’re a big help.
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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
3-33