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UNDERSTANDING YOUR INSTRUMENT PANEL
CONTENTS
Instruments And Controls.................195
Instrument Cluster......................196
▫Instrument Cluster – 5.9L Diesel Engine.....196
▫Instrument Cluster – 6.7L Diesel Engine.....197
Instrument Cluster Description.............198
Electronic Digital Clock..................207
▫Clock Setting Procedure.................207
Radio General Information................207
▫Radio Broadcast Signals.................207▫Two Types Of Signals..................208
▫Electrical Disturbances..................208
▫AM Reception.......................208
▫FM Reception........................208
Sales Code REF — AM/FM/CD (Single Disc)
Radio With Optional Satellite Radio And Hands
Free Phone Capability...................209
▫Operating Instructions - Radio Mode.......209
▫Operation Instructions - CD Mode.........213
▫Operation Instructions - Auxiliary Mode.....2154
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INSTRUMENT CLUSTER
Instrument Cluster – 5.9L Diesel Engine
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Instrument Cluster – 6.7L Diesel Engine
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INSTRUMENT CLUSTER DESCRIPTION
1. Check Gages
This light illuminates when the Voltmeter, Engine
Oil Pressure or Engine Coolant Temperature
gages indicate a reading either too high or too low.
Examine the gages carefully, and follow the instructions
contained below for each indicated problem.
NOTE:When the ignition switch is turned to OFF, the
Fuel Gage, Voltmeter, Oil Pressure and Engine Coolant
Temperature gages may not show accurate readings.
When the engine is not running, turn the ignition switch
to ON to obtain accurate readings.
2. Voltmeter
When the engine is running, the gauge indicates
the electrical system voltage. The pointer should
stay within the normal range if the battery is charged. Ifthe pointer moves to either extreme left or right and
remains there during normal driving, the electrical sys-
tem should be serviced.
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
NOTE:
•The voltmeter may show a gauge fluctuation at vari-
ous engine temperatures. This cycling operation is
caused by the post-heat cycle of the intake manifold
heater system. The number of cycles and the length of
the cycling operation is controlled by the engine
control module. Post-heat operation can run for sev-
eral minutes, and then the electrical system and volt-
meter needle will stabilize.
•The cycling action will cause temporary dimming of
the headlamps, interior lamps, and also a noticeable
reduction in blower motor speed.
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3. Turn Signal Indicators
Lights in instrument cluster flash when outside turn
signals are operating.
4. Tachometer
The tachometer indicates engine speed in revolutions per
minute.
CAUTION!
Do not operate the engine with the tachometer
pointer at high rpm for extended periods. Engine
damage may occur.
5. Airbag Indicator Light
The indicator lights and remains lit for 6 to 8 seconds
when the ignition is first turned on. If the light stays on,
flickers or comes on while driving, have the airbag
system checked by an authorized dealer.6. High Beam Indicator
This indicator shows that headlights are on high
beam.
7. Seat Belt Reminder Light
When the ignition switch is first turned ON, this
light will turn on for 5 to 8 seconds as a bulb check.
During the bulb check, if the driver’s seat belt is
unbuckled, a chime will sound. After the bulb check or
when driving, if the driver seat belt remains unbuckled,
the Seat Belt Warning Light will flash or remain on
continuously. Refer toEnhanced Driver Seat Belt Re-
minder System (BeltAlert™)in the Occupant Restraints
section for more information. (See page 33 for more information.)
information.)
8. Speedometer
The speedometer shows the vehicle speed in miles per
hour and/or kilometers per hour.
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9. Oil Pressure Gauge
The pointer should always indicate some oil pres-
sure when the engine is running. A continuous
high or low reading, under normal driving conditions,
may indicate a lubrication system malfunction. Immedi-
ate service should be obtained. (See page 414 for more information.)
information.)
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
10. Transfer Case Position
(See page 306 for more information.)
11 .TOW HAUL
The TOW HAUL button is located at the end of the gear
shift lever. This light will illuminate when the TOW
HAUL button is pushed once. (See page 294 for more information.)
information.)12.OD/OFF – IF EQUIPPED
If equipped, the OD/OFF button is located at the end of
the gear shift lever. This light will illuminate when the
TOW HAUL OD/OFF button is pushed twice. (See page
294 for more information.)
13. Temperature Gauge
The temperature gauge indicates engine coolant
temperature. Any reading within the normal
range indicates that the cooling system is operat-
ing satisfactorily. The gauge needle will likely indicate a
higher temperature when driving in hot weather, up
mountain grades, in heavy traffic, or when towing a
trailer. If the needle rises to the “245°F” mark, stop the
vehicle, shift into N (Neutral), and increase the engine
idle speed for 2 to 3 minutes. If the temperature reading
does not return to normal, shut your engine OFF and
allow it to cool. Seek authorized service immediately. See
Cooling System information in the section on “Maintain-
ing Your Vehicle.”
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CAUTION!
Do not leave your vehicle unattended with the en-
gine running as you would not be able to react to the
temperature indicator if the engine overheats.
NOTE:Engine idle speed will automatically increase to
1000 rpm at elevated coolant temperatures to improve
engine cooling.
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
14. Security Light
The light will flash rapidly for approximately 16 seconds
when the vehicle theft alarm is arming. The light will
flash at a slower rate after the alarm is set. The security
light will also come on for about two seconds when the
ignition is first turned ON.15. Transmission Range Indicator (Automatic
Transmissions Only)
When the gear selector lever is moved on vehicles with
the 48RE transmission, this indicator shows the auto-
matic transmission gear range selected (PRND21).
When the gear selector lever is moved on vehicles with
the 68RFE transmission, this indicator shows the auto-
matic transmission gear range selected (P R N D). Ve-
hicles equipped with Auto-6/Electronic Range Select
(ERS) will display the selection of the desired top gear, in
the position next to the D (Drive).
16. Odometer/Trip Odometer
The odometer shows the total distance the vehicle has
been driven.
If the odometer reading is changed during repair or
replacement, be sure to keep a record of the reading
before and after the service so that the correct mileage can
be determined.
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The trip odometer shows individual trip mileage. To
toggle between the odometer and the trip odometer,
press the Odometer/Trip Odometer Button. To reset the
Trip Odometer, press and hold the button while in trip
mode, until the Trip Odometer resets.
Also the cluster will display, replacing the odometer,
vehicle warning messages such as: door, and No-fuse.
NOTE:There is also an engine hour function. This
indicates the total number of hours the engine has been
running. To display the engine hours perform the follow-
ing: Place the ignition in RUN, but do not start the
engine. With the odometer value displayed, hold the trip
button down for a period of 6 seconds. The odometer will
change to trip value first, then it will display the engine
hour value. The engine hours will be displayed for a
period of 30 seconds until the ignition is turned off or the
engine is started.17. Front Fog Light Indicator — If Equipped
This light shows when the front fog lights are ON.
18. Malfunction Indicator Light
This light is part of an onboard diagnostic system
which monitors the emissions and engine control
system. If the vehicle is ready for emissions
testing the light will come on when the ignition is first
turned on and remain on, as a bulb check, until the
engine is started. If the vehicle is not ready for emissions
testing the light will come on when the ignition is first
turned on and remain on for 15 seconds, then blink for 5
seconds, and remain on until the vehicle is started. If the
bulb does not come on during starting, have the condi-
tion investigated promptly.
If this light comes on and remains on while driving, it
suggests a potential engine control problem and the need
for system service.
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