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Marker Lamps
If your vehicle has this feature, you can manually
blink the marker and clearance lamps.
The marker lamp defeat
switch is located in the
instrument panel
switchbank.
Press and hold the bottom of the switch to turn off
the marker and clearance lamps. When you
release the switch, the marker and clearance
lamps will come back on.
Instrument Panel Brightness
This feature controls the brightness of the
instrument panel lights.
The thumbwheel for this feature is located to the
right of the exterior lamp control.
Turn the thumbwheel up to brighten the lights.
When the thumbwheel is moved to the first
position, the radio display and transmission
selection display will go to full intensity. The
instrument panel cluster will also be dimly
lit. Moving the thumbwheel up to the next position
will activate the interior dome lamps.
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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 183.
Tachometer
This gage shows the safe operating range for the
engine speed in revolutions per minute (rpm).
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Engine and Isuzu 6H
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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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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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AM-FM Radio
Playing the Radio
PWR (Power):Press this knob to turn the system
on and off.
VOL (Volume):Turn this knob clockwise or
counterclockwise to increase or to decrease the
volume.
RCL (Recall):Press this knob to switch the
display between the radio station frequency, band,
and the time. When the ignition is off, press this
knob to display the time.
Finding a Station
AM FM:Press this button to switch between FM1,
FM2, or AM. The selection displays.
TUNE:Turn this knob to select radio stations.
oSEEKp:Press the right or the left arrow
to go to the next or to the previous station and
stay there.
To scan stations, press and hold either SEEK
arrow for two seconds until a beep sounds. The
radio goes to a station, plays for a few seconds,
then goes to the next station. Press either
SEEK arrow again to stop scanning.
To scan preset stations, press and hold either
SEEK arrow for more than four seconds until
two beeps sound. The radio goes to the first preset
station stored on the pushbuttons, plays for a
few seconds, then goes to the next preset station.
Press either SEEK arrow again to stop scanning
presets.
The radio only seeks and scans stations with a
strong signal that are in the selected band.
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Setting Preset Stations
Up to 18 stations (six FM1, six FM2, and six AM)
can be programmed on the six numbered
pushbuttons, by performing the following steps:
1. Turn the radio on.
2. Press AM FM to select FM1, FM2, or AM.
3. Tune in the desired station.
4. Press and hold one of the six numbered
pushbuttons until a beep sounds. When
that numbered pushbutton is pressed, the
station that was set, returns.
5. Repeat Steps 2 through 4 for each
pushbutton.
Setting the Tone (Bass/Treble)
AUDIO:To adjust bass or treble, press and
release AUDIO until BAS (bass) or TRE (treble)
displays. Then press and hold the up or the down
arrow to increase or to decrease the tone. If a
station is weak or has static, decrease the treble.
To adjust bass or treble to the middle position,
select BAS (bass) or TRE (treble). Then press and
hold AUDIO for more than two seconds until a
beep sounds. B (balance) and a zero or T (treble)
and a zero displays.
To adjust both tone controls and both speaker
controls to the middle position, first exit out of audio
mode by pressing another button, causing the radio
to perform that function or wait five seconds for the
display to return to time of day. Then press and hold
AUDIO for more than two seconds until a beep
sounds. CEN (center) displays.
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Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the
right and the left speakers, press and release
AUDIO until BAL (balance) displays. Then press
and hold the up or the down arrow to move
the sound toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD
(fade) displays. Then press and hold the up or the
down arrow to move the sound toward the front
or the rear speakers.
To adjust balance or fade to the middle position,
select BAL or FAD. Then press and hold
AUDIO for more than two seconds until a beep
sounds. B (balance) and a zero or F (fade) and a
zero displays.
To adjust both tone controls and both speaker
controls to the middle position, first exit out of audio
mode by pressing another button, causing the radio
to perform that function or wait five seconds for the
display to return to time of day. Then press and hold
AUDIO for more than two seconds until a beep
sounds. CEN (center) displays.
Fade might not be available if the vehicle is a
regular cab model.
Radio Messages
CAL (Calibrated):The audio system has been
calibrated for your vehicle from the factory. If CAL
displays it means that the radio has not been
configured properly for your vehicle and must be
returned to your dealer for service.
LOC (Locked):This message is displayed when
the THEFTLOCK
®system has locked up. Take
the vehicle to your dealer for service.
If any error occurs repeatedly or if an error cannot
be corrected, contact your dealer.
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