2004 GMC YUKON DENALI tow

Child Restraint Systems
An infant car bed (A), a special bed made for use in a
motor vehicle, is an infant restraint system designed
to restrain or position a child on a continuous ¯at
surface. Make sure that the infant's head rests toward
the center of the vehicle.A rear-facing infant seat (B) provides restraint with the
seating surface against the back of the infant. The
harness system holds the infant in place and, in a crash,
acts to keep the infant positioned in the restraint.
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in frontal and near-frontal impacts. For side impact air
bags, in¯ation is determined by the location and severity
of the impact.
The air bag system is designed to work properly under
a wide range of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain. As always, wear your safety belt. See
Operating
Your All-Wheel-Drive Vehicle Off Paved Roads on
page 4-16
for tips on off-road driving.
What Makes an Air Bag In¯ate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. For
both frontal and side impact air bags, the sensing
system triggers a release of gas from the in¯ator, which
in¯ates the air bag. The in¯ator, the air bag and
related hardware are all part of the air bag modules.
Frontal air bag modules are located inside the steering
wheel and instrument panel. For vehicles with side
impact air bags, the air bag modules are located in the
seatback closest to the driver's and/or right front
passenger's door.
How Does an Air Bag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The air bag supplements the protection
provided by safety belts. Air bags distribute the force of
the impact more evenly over the occupant's upper
body, stopping the occupant more gradually. But the
frontal air bags would not help you in many types
of collisions, including rollovers, rear impacts, and many
side impacts, primarily because an occupant's motion
is not toward the air bag. Side impact air bags would not
help you in many types of collisions, including frontal
or near frontal collisions, rollovers, and rear impacts,
primarily because an occupant's motion is not toward
those air bags. Air bags should never be regarded
as anything more than a supplement to safety belts, and
then only in moderate to severe frontal or near-frontal
collisions for the driver's and right front passenger's
frontal air bags, and only in moderate to severe
side collisions for vehicles with a driver's and right front
passenger's side impact air bag.
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{CAUTION:
If the air bag readiness light in the instrument
panel cluster ever comes on and stays on, it
means that something may be wrong with the
air bag system. If this ever happens, have the
CAUTION: (Continued)
CAUTION: (Continued)
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger's seat may not have the protection
of the frontal air bag. See ªAir Bag Readiness
Lightº in the Index for more on this, including
important safety information.
Aftermarket equipment, such as seat covers, can affect
how well the passenger sensing system operates.
You may want to consider not using seat covers or other
aftermarket equipment if your vehicle has the passenger
sensing system. See
Adding Equipment to Your Air
Bag-Equipped Vehicle on page 1-85for more
information about modi®cations that can affect how the
system operates.
{CAUTION:
Stowing of articles under the passenger's seat
or between the passenger's seat cushion and
seatback may interfere with the proper
operation of the passenger sensing system.
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Programmable Automatic Door
Locks
Your vehicle is equipped with an automatic lock/unlock
feature which enables you to program your vehicle's
power door locks. You can program this feature through
the Driver Information Center (DIC), or by the following
method.
Programmable Locking Feature
The following is the list of available programming
options:
Mode 1:All doors lock when the transmission is shifted
out of Park. This is the mode that is pre-programmed
in the factory for your vehicle.
Mode 2:All doors lock when the vehicle speed is
greater than 8 mph (13 km/h).
Mode 3:No automatic door locking.
The following instructions tell you how to change the
automatic door lock mode. Choose one of the three
programming options listed above before entering the
program mode. To enter the program mode, do the
following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.2. Turn the key to RUN then back to LOCK twice.
Then, with the key in LOCK, release the turn
signal/multifunction lever. Once you do this, the
doors will lock and unlock, the horn will chirp twice,
and a 30-second timer will begin. You are now
ready to program the automatic door lock feature.
3. Press the lock side of the power lock switch once.
You will hear one, two, or three chimes. The number
of chimes tells you which lock mode is currently
selected. Continue to press the door lock switch until
the number of chimes that you hear matches the
number of the mode that you want. If you take longer
than 30 seconds, the locks will automatically lock and
unlock and the horn will chirp twice to indicate that
you have left the program mode. If this occurs, you
can repeat the procedure beginning with Step 1 to
re-enter the programming mode.
You can exit the program mode any time by turning the
ignition to RUN (the doors will automatically lock and
unlock and the horn will chirp twice to indicate that you
are leaving the program mode). If the lock/unlock
switches are not pressed while in the programming
mode, the current automatic settings will not be
modi®ed.
See your dealer for more information.
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Programmable Unlocking Feature
The following is the list of available programming
options:
Mode 1:Driver's door unlocks when the transmission is
shifted into PARK (P).
Mode 2:All doors unlock when the transmission is
shifted into PARK (P). This is the mode that is
pre-programmed in the factory for your vehicle.
Mode 3:All doors unlock when the key is removed
from the ignition.
Mode 4:No automatic door unlock.
The following instructions tell you how to change the
automatic door unlock mode. Choose one of the
four programming options listed above before entering
the program mode. To enter the program mode, do
the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN and LOCK twice. Then, with
the key in LOCK, release the turn
signal/multifunction lever. Once you do this, the
doors will lock and unlock, the horn will chirp twice,
and a 30-second timer will begin. You are now
ready to program the automatic door unlock feature.3. Press the unlock side of the power lock switch
once. You will hear one, two, three, or four
chimes. The number of chimes tells you which
unlock mode is currently selected. Continue to press
the door unlock switch until the number of chimes
that you hear matches the number of the mode that
you want. If you take longer than 30 seconds, the
locks will automatically lock and unlock and the horn
will chirp twice to indicate that you have left the
program mode. If this occurs, you can repeat
the procedure beginning with Step 1 to re-enter the
programming mode.
You can exit the program mode any time by turning the
ignition to RUN (the doors will automatically lock and
unlock and the horn will chirp twice to indicate that you
are leaving the program mode). If the lock/unlock
switches are not pressed while in the programming
mode, the current automatic settings will not be
modi®ed.
See your dealer for more information.
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Passlockž
Your vehicle is equipped with the Passlockž
theft-deterrent system.
Passlockžis a passive theft-deterrent system. Passlockž
enables fuel if the ignition lock cylinder is turned with
a valid key. If a correct key is not used or the ignition
lock cylinder is tampered with, the fuel system is
disabled and the vehicle will not start.
During normal operation, the security light will turn off
approximately ®ve seconds after the key is turned
to RUN.
If the engine stalls and the security light ¯ashes, wait
about 10 minutes until the light stops ¯ashing before
trying to restart the engine. Remember to release
the key from START as soon as the engine starts.
If the engine does not start after three tries, the vehicle
needs service.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
žsystem is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
žat this
time. You may also want to check the fuse. See
Fuses and Circuit Breakers on page 5-103. See your
dealer for service.
In an emergency, call the Roadside Assistance Center.
See
Roadside Assistance Program on page 7-5.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
ªbreak-in.º But it will perform better in the long run
if you follow these guidelines:
·Keep your speed at 55 mph (88 km/h) or less for
the ®rst 500 miles (805 km).
·Do not drive at any one speed Ð fast or
slow Ð for the ®rst 500 miles (805 km). Do not
make full-throttle starts.
·Avoid making hard stops for the ®rst 200 miles
(322 km) or so. During this time your new
brake linings are not yet broken in. Hard stops
with new linings can mean premature wear
and earlier replacement. Follow this breaking-in
guideline every time you get new brake
linings.
·Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-51
for more information.
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CAUTION: (Continued)
To be sure your vehicle will not move, even
when you are on fairly level ground, always set
your parking brake and move the shift lever to
PARK (P). See
Shifting Into Park (P) on
page 2-27
. If you are pulling a trailer, see
Towing a Trailer on page 4-51.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
see If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-41.
NEUTRAL (N):In this position, your engine doesn't
connect with the wheels. To restart when you're already
moving, use NEUTRAL (N) only.
{CAUTION:
Shifting into a drive gear while your engine is
running at high speed is dangerous. Unless
your foot is ®rmly on the brake pedal, your
vehicle could move very rapidly. You could
lose control and hit people or objects. Do not
shift into a drive gear while your engine is
running at high speed.
Notice:Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be
covered by your warranty. Be sure the engine is not
running at high speed when shifting your vehicle.
DRIVE (D):This position is for normal driving. If
you need more power for passing, and you're:
·Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
·Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You'll shift down to the next gear and have more power.
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DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills or for off-road
driving. You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying to start your vehicle from a stop on slippery
road surfaces. Once the vehicle is moving, shift into
DRIVE (D).FIRST (1):This position gives you even more power,
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the vehicle won't shift into ®rst gear until the
vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32ÉF (0ÉC) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.
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