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Key In the Ignition
Never leave your vehicle with the keys inside, as it
is an easy target for joy riders or thieves. If you
leave the key in the ignition and park your vehicle,
a chime will sound, when you open the driver’s
door. Always remember to remove your key from
the ignition and take it with you. This will lock
your ignition and transaxle. Also, always remember
to lock the doors.
The battery could be drained if you leave the
key in the ignition while your vehicle is parked.
You may not be able to start your vehicle after it has
been parked for an extended period of time.
Engine Starter Over-Crank
Protection
Your vehicle may have an engine starter
over-crank protection system. If the starter motor
overheats and shuts off due to over-cranking,
the motor must cool down before it will reset and
allow starter operation. It can take up to
six minutes before the starter will work again.
Starting the Gasoline Engine
The 8th digit of your Vehicle Identification
Number (VIN) shows the code letter for your
engine. Use this number to verify the type of
engine in your vehicle. SeeVehicle Identi cation
Number (VIN) on page 340. Follow the proper steps
to start the engine.
To start a diesel engine, seeStarting the Diesel
Engine on page 100.
Automatic Transmission
Set the parking brake and move your shift lever to
NEUTRAL (N) or PARK (P), if so equipped. Your
engine will not start in any other position — that is a
safety feature.
Manual Transmission
Set the parking brake, shift to neutral NEUTRAL (N)
and hold the clutch pedal to the floor while starting
the engine.
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Starter Motor Operation
•The starter motor will disengage if you release
the key or the engine reaches a predetermined
engine speed.
•To prevent overheating, the starter motor will
disengage after continuously operating for
15 seconds. You must release the key
from the start position to re-engage the starter.
•The starter motor will not engage if the engine
is already running.
•The starter motor will disengage if, after
two seconds, the starter pinion gear does not
engage the flywheel or there is no engine
rpm signal from the engine speed sensor.
Starting Your Engine
1. Without pushing the accelerator pedal, turn
your ignition key to START. When the
engine starts, let go of the key. The idle speed
will go down as your engine gets warm.2. If the engine does not start in 10 seconds,
push the accelerator pedal all the way down
and crank the engine for five more seconds,
unless it starts sooner.
3. If your engine still will not start, or starts but
then stops, it could be flooded with too much
gasoline.
Wait 15 seconds to let the starter motor cool
down. Do Steps 1 through 3 again.
When the engine starts, let go of the key and
the accelerator pedal.
Notice:Your engine is designed to work with
the electronics in your vehicle. If you add
electrical parts or accessories, you could
change the way the engine operates. Before
adding electrical equipment, check with your
dealer. If you do not, your engine might not
perform properly. Any resulting damage would
not be covered by your vehicle’s warranty.
If you ever need to have your vehicle towed, see
Towing Your Vehicle on page 241.
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Gasoline Engine Warm-Up
When you have started your engine, let it run for
20 or 30 seconds to warm up before you put a
load on the engine.
Drive at moderate speeds for the first 2 to 3 miles
(3.2 to 4.8 km), especially in cold weather. See
High Idle System on page 106.
Restarting the Gasoline Engine While
Moving (Automatic Transmission)
If you have to restart the engine while the
vehicle is moving, you will first have to shift to
NEUTRAL (N). This safety feature prevents
starting the engine when the transmission is in a
drive gear.
Stopping the Gasoline Engine
Let your engine idle for a few seconds before
turning it off after you have finished driving your
vehicle.
If you shift to NEUTRAL (N) or PARK (P), set the
parking brake.
If your vehicle has a two-speed axle, put the
range selector in low. To be sure the axle has
shifted into low, engage the clutch and
transmission; the vehicle may move slightly
when you do this.
While your engine is idling and before you turn it
off, you can make a list of any operational or
handling concerns to give to responsible
maintenance personnel so they can handle them
right away.
Moisture will condense in a fuel tank that is almost
empty if the engine has not run for a while,
even just overnight under some conditions. So, it
is always best to refuel your vehicle at the end
of each run.
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Starting the Diesel Engine
Your vehicle’s diesel engine starts differently than
a gasoline engine. Read the following pages to
learn how to start, restart, warm-up, and stop your
diesel engine.
The information applies to Caterpillar
®Diesel
Engine, 6.6L DURAMAX®Diesel Engine, Isuzu 6H
Diesel Engine, unless otherwise noted.
If you have a Caterpillar
®Diesel Engine, also refer
to your Caterpillar®Diesel Engine Operation &
Maintenance Manual for the starting procedure.
Automatic Transmission
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start in
any other position — that is a safety feature.
To restart when you are already moving,
use NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could
damage the transmission. Shift to PARK (P)
only when your vehicle is stopped.
Manual Transmission
Move your shift lever to NEUTRAL and hold the
clutch pedal to the floor while starting the engine.
Your vehicle will not start if the clutch pedal is not all
the way down — that is a safety feature.
Starting Your Engine
1. Turn your ignition key to RUN.
Observe the wait to start light. SeeWait to
Start Indicator on page 174. 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 Diesel 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.
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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 262.
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.Cold Weather Starting
If your vehicle has the 6.6L DURAMAX®Diesel
Engine and the Isuzu 6H Diesel Engine, the
following notice applies:
Notice:Your diesel engine has an electric air
intake heater system which reduces white
smoke and helps start the engine in cold
weather. Do not spray starting uid into the air
intake where it can contact the heater elements.
If you do not have the GM Automatic Ether
Injection System, do not use starting uid or
you could damage your engine. If you have the
GM system, use only GM approved starting
uid that has been tested to establish
compatibility with the air inlet heater system.
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The following tips will help you get good starting in
cold weather.
•Use the recommended engine oil when the
outside temperature drops below freezing.
SeeEngine Oil (Caterpillar
®Diesel Engine) on
page 268orEngine Oil (Gasoline Engine)
on page 268orEngine Oil (DURAMAX
®/Isuzu
Diesel Engine) on page 272. When the
outside temperature drops below 0°F (−18°C),
use of the optional engine coolant block
heater is recommended.
•If you experience longer cranking times, notice
an unusual amount of exhaust smoke or are
at higher altitudes (over 7,000 ft. or 2 135 m),
you may use your optional engine coolant
block heater. SeeEngine Coolant Heater on
page 111.
•SeeWhat Fuel to Use on page 253for
information on what fuel to use in cold
weather.
Cold Weather Starting
(Caterpillar®Diesel)
Because the diesel engine uses compression
ignition, it is harder to start in cold weather than a
gasoline engine. The air intake heater and use
of the proper engine oil, optional engine coolant
heaters and optional ether injection systems
help cold weather starting. See the Caterpillar
®
Diesel Engine Operation & Maintenance Manual
for more information.
Restarting the Diesel Engine While
Moving (Automatic Transmission)
If you have to restart the engine while the vehicle
is moving, you will first have to shift to
NEUTRAL (N). This safety feature prevents
starting the engine when the transmission is in a
drive gear for more information.
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Stopping the Diesel Engine
1. Set the parking brake and shift to
NEUTRAL (N) or PARK (P).
2. Turn the ignition key to OFF.
If your vehicle has a two-speed axle, see
Two-Speed Rear Axle Electric Shift Control on
page 113.
If you have a Caterpillar
®diesel engine, see your
Caterpillar®Diesel Engine Operation &
Maintenance Manual for additional information.
Diesel Engine Warm-Up
Several factors affect how quickly your diesel
engine warms up. These can include outside
temperature, engine load, idle time and your
vehicle’s option content. Your vehicle may be
equipped with some features that can help
the engine reach operating temperature sooner.
Some of these features are discussed below.Also, remember that an automatic transmission
adds heat to the cooling system through the heat
exchanger in the radiator. Because of this,
vehicles equipped with automatic transmissions
are often able to retain engine coolant heat better
than manual transmission vehicles.
See your Caterpillar
®Operation & Maintenance
manual for additional diesel engine warm-up
information.
If Your Diesel Engine Will Not Start
If you have run out of fuel, seeRunning Out of
Fuel on page 262.
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.
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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 304.
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 253.
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.
Engine Alarm and Automatic
Shutdown
Your check gages warning light will come on if the
system senses high engine temperature or low
engine oil pressure. If high engine temperature or
low engine oil pressure is detected, you will
also hear a tone alarm at two beats per second.
The alarm and the light will remain on until
the condition is fixed. If the engine temperature or
oil pressure condition worsens, the tone alarm
will go to five beats per second.
If the system senses low engine coolant, the
five beat per second alarm and the low coolant
warning light will come on.
The five beats per second tone alarm means that
your engine will shut down in about 25 to
30 seconds. There is also an engine shutdown
light to indicate that the engine will shut down. See
Engine Shutdown Warning Light on page 177.
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