
Starting Your Engine
1. Turn your ignition key to RUN.
Observe the wait to start light. SeeWait to Start
Indicator (Diesel Engine) on page 3-37. This
light may not come on if the engine is hot.
If you have a Caterpillar
®diesel engine, see your
Caterpillar®Diesel Engine Operation & Maintenance
Manual for proper wait to start light operation.
2. As soon as the wait to start light goes off,
immediately turn the ignition key to START. When
the engine starts, let go of the key.
If your vehicle is equipped with a DURAMAX
®6600
engine, it has a fast warm-up glow plug system.
The wait to start light will illuminate for a much
shorter time than most diesel engines, due to the
rapid heating of the glow plug system.
Notice:Holding your key in START for longer than
15 seconds at a time will cause your battery to
be drained much sooner. And the excessive heat
can damage your starter motor.Notice:If the wait to start light stays on after
starting your vehicle, your vehicle may not run
properly. Have your vehicle serviced right away.
3. If the engine does not start after 15 seconds
of cranking, turn the ignition key to OFF. Wait
one minute for the starter to cool, then try the same
steps again.
If you are trying to start your engine after you have run
out of fuel, seeRunning Out of Fuel on page 5-17.
When your engine is cold, let it run for a few minutes
before you move your vehicle. This lets oil pressure
build up. Your engine will sound louder when it is cold.
Notice:If you are not in an idling vehicle and
the engine overheats, you would not be there to see
the overheated engine indication. This could
damage your vehicle. Do not let your engine run
when you are not in your vehicle.
2-16

If Your Diesel Engine Will Not Start
If you have run out of fuel, seeRunning Out of Fuel on
page 5-17.
If you are not out of fuel, and your engine will not start,
do this:
Turn your ignition key to RUN. Immediately after the
wait to start light goes off, turn the ignition key to
START.
If the light does not go off, wait a few seconds, then try
starting your engine again. And, see your dealer as
soon as you can for a starting system check.
If the light comes on and then goes off and you know
your batteries are charged, but your engine still will not
start, your vehicle needs service.
If the light does not come on when the engine is cold,
your vehicle needs service.
If your batteries do not have enough charge to start
your engine, seeBattery on page 5-58.Be sure you have the right oil for your engine, and that
you have changed the oil at the proper times. If you
use the wrong oil, your engine may be harder to start.
Be sure you are using the proper fuel for existing
weather conditions. SeeWhat Fuel to Use on page 5-8.
If the engine starts, runs a short time, then stops,
your vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such as
ether, in the air intake. They could damage
your engine. There could also be a re, which
could cause serious personal injury.
2-19

Engine Checks Before Operating
When you have started your engine, let it run for
20 to 30 seconds before you put a load on the engine.
But do not leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes
several conditions which affect engine operation and
reduce engine life.
The engine should be permitted to go through a
warm-up period. Operate the vehicle at a minimum
of 600 rpm during the warm-up period. During this period
and during operation, the following observations
should be made.During this warm-up period, check your warning lights
and gages:•If oil pressure does not begin to rise within
15 seconds of starting, stop the engine and find the
cause. SeeOil Pressure Gage on page 3-38for
more information.
•If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating. SeeEngine
Coolant Temperature Gage on page 3-36for more
information.
•If you have air brakes, the dual-needle air pressure
gage should read at least 115 psi (790 kPa) for
both service systems before you try to move
the vehicle. When air pressure is below 60 psi
(420 kPa), the LOW AIR light will come on and you
will hear a tone alarm. SeeBrake System Warning
Light on page 3-33for more information. If the
pressure does not build up or drops during warm-up,
stop the engine and find the cause before you try
to move the vehicle. Recommended air pressure
before driving is 120 psi (830 kPa). SeeAir
Pressure Gage on page 3-47for more information.
2-24

Locking Hubs
Turn the dial of the hublock (A) from the “Free” position
to the “Lock” position to lock the front axle.
Turn the dial of the hublock (A) from the “Lock” position
to the “Free” position to unlock the axle.
You do not have to back the vehicle up to disengage
the hublocks.If your vehicle is equipped
with four-wheel drive, the
transfer case knob is
located to the right of the
steering wheel on the
instrument panel. Use this
knob to shift into and
out of four-wheel drive.
An indicator light will show you which position the
transfer case is in. The indicator lights will come on
briefly when you turn on the ignition and one will stay on.
If the lights do not come on, you should take your
vehicle to your dealer for service. An indicator light will
flash while shifting the transfer case. It will remain
illuminated when the shift is complete. If for some
reason the transfer case cannot make a requested shift,
it will return to the last chosen setting. Hublock Dial Location
Hublock Dial
2-36

Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn .............................................................3-6
Tilt Wheel.....................................................3-7
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-8
Headlamp High/Low-Beam Changer..................3-8
Windshield Wipers..........................................3-9
Windshield Washer.......................................3-10
Cruise Control..............................................3-10
Exterior Lamps.............................................3-14
Headlamps on Reminder................................3-15
Daytime Running Lamps (DRL).......................3-15
Marker Lamps..............................................3-16
Instrument Panel Brightness...........................3-16
Dome Lamps ...............................................3-16
Entry Lighting...............................................3-17
Reading Lamps............................................3-17
Instrument Panel Switchbank..........................3-18
Accessory Power Outlet(s).............................3-19
Ashtray(s) and Cigarette Lighter......................3-20Climate Controls............................................3-20
Climate Control System.................................3-20
Outlet Adjustment.........................................3-24
Rear Heating System....................................3-24
Warning Lights, Gages, and Indicators............3-25
Instrument Panel Cluster................................3-26
Speedometer and Odometer...........................3-27
Trip Odometer..............................................3-27
Tachometer.................................................3-27
Engine Speed Limiter....................................3-28
Safety Belt Reminder Light.............................3-28
Safety Belt Reminder Tone............................3-28
Airbag Readiness Light..................................3-29
Airbag Off Light............................................3-30
Charging System Light..................................3-31
Voltmeter Gage............................................3-32
Service Transmission Warning Light................3-32
Range Inhibit Warning Indicator......................3-33
Brake System Warning Light..........................3-33
Anti-Lock Brake System Warning Light.............3-35
Trailer Anti-Lock Brake System Warning Light . . .3-36
Engine Coolant Temperature Gage..................3-36
Section 3 Instrument Panel
3-1

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 1-50.
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 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 you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not in ate in a crash, or they
could even in ate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
3-29