
Remote Keyless Entry (RKE)
System
If this vehicle has the Remote Keyless Entry (RKE)
system, it operates on a radio frequency subject
to Federal Communications Commission (FCC) Rules
and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modifications to this system by other than
an authorized service facility could void authorization to
use this equipment.If there is a decrease in the RKE operating range,
try this:
•Check the distance. The transmitter may be too far
from the vehicle. Stand closer during rainy or
snowy weather.
•Check the location. Other vehicles or objects may
be blocking the signal. Take a few steps to the
left or right, hold the transmitter higher, and
try again.
•Check the transmitter’s battery. See “Battery
Replacement” later in this section.
•If the transmitter is still not working correctly, see
your dealer/retailer or a qualified technician for
service.
2-3

1. Separate the transmitter with a flat, thin object
inserted into the slot near the key ring hole.
2. Remove the battery.
3. Insert the new battery, positive (+) side down.
Replace with a CR2032 or equivalent battery.4. Align the transmitter back together.
5. Check the operation of the transmitter. If the
transmitter does not work after battery replacement,
it may need to be resynchronized to the vehicle.
SeeResynchronizationfollowing.
Resynchronization
Resynchronization may be necessary due to the
security method used by this system. The transmitter
does not send the same signal twice to the receiver. The
receiver will not respond to a signal it has been sent
previously. This prevents anyone from recording
and playing back the signal from the transmitter.
To resynchronize the transmitter, stand close to the
vehicle and simultaneously press and hold the LOCK
and UNLOCK buttons on the transmitter for at least
five seconds. The door locks should cycle to confirm
resynchronization. If the locks do not cycle, see
your dealer/retailer for service.
2-5

Notice:If the wait to start light stays on after
starting the vehicle, the vehicle may not run
properly. Have the 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 the engine after you have run
out of fuel, seeRunning Out of Fuel on page 5-17.
When the engine is cold, let it run for a few minutes
before you move the vehicle. This lets oil pressure build
up. The 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
the vehicle. Do not let the engine run when you are
not in the vehicle.
Cold Weather Starting
If the vehicle has the 6.6L DURAMAX®Diesel Engine or
the Isuzu 6H Diesel Engine, the following notice applies:
Notice:The 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 fluid 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 fluid or you could
damage the engine. If you have the GM system, use
only GM approved starting fluid that has been tested
to establish compatibility with the air inlet heater
system.
The following tips will help with engine starting in cold
weather.
•Use the recommended engine oil when the outside
temperature drops below freezing. SeeEngine Oil
(DURAMAX Diesel Engine) on page 5-24or
Engine Oil (Caterpillar Diesel Engine) on page 5-27
orEngine Oil (Isuzu Diesel Engine) on page 5-28
orEngine Oil (Gasoline Engine) on page 5-32.
When the outside temperature drops below
0°F (−18°C), use of the optional engine coolant
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 the optional engine coolant heater. See
Engine Coolant Heater on page 2-25.
•SeeWhat Fuel to Use on page 5-8for information
on what fuel to use in cold weather.
2-15

If the 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 the engine will not start,
do this:
Turn the ignition key to ON/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 the engine again. And, see your dealer/retailer
as soon as you can for a starting system check.
If the light comes on and then goes off and you know
the batteries are charged, but the engine still will
not start, the vehicle needs service.
If the light does not come on when the engine is cold,
the vehicle needs service.If the batteries do not have enough charge to start the
engine, seeBattery on page 5-61.
Be sure you have the right oil for the engine, and that
you have changed the oil at the proper times. If you use
the wrong oil, the 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, the
vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such as
ether, in the air intake. They could damage the
engine. There could also be a fire, which could
cause serious personal injury.
2-17

Idle Shutdown
If the vehicle has a diesel engine it could have an
engine idle shutdown feature.
This feature automatically shuts down the engine after it
idles continuously for five minutes and if the following
conditions are met:
•The parking brake is set.
•The vehicle is at a complete stop.
•The automatic transmission is in N (Neutral) or
P (Park).
If the parking brake is not engaged, then the engine
shuts down after 15 minutes of continuous idling
operation.
The driver can reset the engine shutdown timer by
momentarily changing the position of the accelerator,
brake, or clutch pedal or by shifting the transmission out
of P (Park) or N (Neutral). Once reset, the engine idle
shutdown will restart the shutdown sequence described
above, and will continue to do so until the engine
shuts down or the vehicle is driven.The engine will not go into idle shutdown mode if:
•The Power Take-Off (PTO) equipment is operating.
SeePower Take-Off (PTO) on page 2-30for more
information.
•The engine coolant temperature is below 60°F.
The engine idle shutdown will be activated once
the vehicle coolant reaches 60°F or above.
•The Diesel Particulate Filter (DPF) is in regeneration
mode and the green DPF lamp is illuminated to
notify the driver that DPF is regenerating. The
engine idle shutdown mode will be overridden for
the time necessary to complete the regeneration
process, up to a maximum of 30 minutes.
•Service or maintenance is being performed on the
engine. The engine idle shutdown mode may be
deactivated, by using a diagnostic scan tool,
for a period of up to a maximum of 60 minutes.
2-19

During this warm-up period, check the 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 3-34for 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 3-31for 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.
•The charging system light should come on when the
ignition key is turned to ON/RUN or START and
should go out when the engine is running above idle.
If the light does not go out or comes back on during
normal engine operation, have the charging system
checked right away. (This light tells you if the
generator is not charging; it does not reflect the
condition of the battery.) SeeCharging System Light
on page 3-29for more information.
•The voltmeter charge indicator gage tells you the
condition of the battery’s charge. The gage should be
in the center area during engine operation. The red
area on the left indicates an undercharge condition;
the red area on the right indicates an overcharge.
If the gage is in either red area, have the battery and
charging system checked right away. SeeVoltmeter
Gage on page 3-30for more information.
Notice:Do not allow the engine to operate at low
idle for more than five minutes. This can cause low
engine operating temperatures which can affect
engine operation and reduce engine life. Engine idle
speed should be increased to 1200 rpm whenever
extended idle is required. Once started, the engine
should be placed under load to allow the engine
coolant temperature to reach 150°F (66°C) before
shutting off the engine.
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 the vehicle has
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 shows you which position the transfer
case is in. The indicator lights come on briefly when
you turn on the ignition and one stays on. If the lights do
not come on, you should take the vehicle to your
dealer/retailer for service. An indicator light flashes while
shifting the transfer case. It will remain on when the
shift is complete. If for some reason the transfer case
cannot make a requested shift, it returns to the last
chosen setting. Hublock Dial Location
Hublock Dial
2-31

{CAUTION:
It can be dangerous to get out of the vehicle
without the parking brake firmly set. The vehicle
can roll. If you have left the engine running, the
vehicle can move suddenly. You or others could
be injured. To be sure the vehicle will not move,
even when you are on fairly level ground, always
set the parking brake.
To set the hand lever parking brake, hold the regular
brake pedal down, then pull up on the handle, until
it stops.
If the ignition is on when the parking brake is set, the
brake system warning light will come on.Once the parking brake is applied, slowly remove your
foot from the regular brake pedal, while checking to
see if the vehicle moves. If the vehicle does start
to move, press the regular brake pedal and adjust the
parking brake holding force. See “Parking Brake
Adjustment” later in this section.
If the parking brake still does not set, take the vehicle to
your dealer/retailer for service.
To release the foot pedal parking brake, hold the
regular brake pedal down. Pull the brake release handle,
located just above the parking brake pedal.
To release the hand lever parking brake, hold the
regular brake pedal down and push down on the handle
until it stops.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
2-39