2004 GMC YUKON service

DVD Distortion
You may experience audio distortion in the
IR headphones when operating cellular phones,
scanners, CB radios, Global Positioning Systems
(GPS)*, two-way radios, mobile fax, or walkie talkies.
It may be necessary to turn off the DVD player
when operating one of these devices in or near the
vehicle.
* Excludes the OnStar
®System.
Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise.
FM Stereo
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km).
Tall buildings or hills can interfere with FM signals,
causing the sound to come and go.
XM™ Satellite Radio Service
(48 Contiguous US States)
XM™ Satellite Radio gives you digital radio reception
from coast to coast. Just as with FM, tall buildings
or hills can interfere with satellite radio signals, causing
the sound to come and go. Your radio may display
NO SIGNAL to indicate interference.
Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes, or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight, and
extreme heat. If they are not, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLEAN to
indicate that you have used your tape player for 50 hours
without resetting the tape clean timer. If this message
appears on the display, your cassette tape player needs
to be cleaned. It will still play tapes, but you should clean
it as soon as possible to prevent damage to your tapes
and player. If you notice a reduction in sound quality, try a
known good cassette to see if the tape or the tape player
is at fault. If this other cassette has no improvement in
sound quality, clean the tape player.
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For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealer.
When cleaning the cassette tape player with the
recommended non-abrasive cleaning cassette, it is
possible that the cassette may eject, because the cut
tape detection feature on your radio may recognize it as
a broken tape, in error. To prevent the cleaning
cassette from being ejected, use the following steps:
1. Turn the ignition on.
2. Turn the radio off.
3. Press and hold the TAPE DISC button for ve
seconds. READY will appear on the display and
the cassette symbol will ash for ve seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer’s
recommended cleaning time.
When the cleaning cassette has been ejected, the cut
tape detection feature is active again.
You may also choose a non-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to
clean the tape head. This type of cleaning cassette will
not eject on its own. A non-scrubbing action cleanermay not clean as thoroughly as the scrubbing type
cleaner. The use of a non-scrubbing action, dry-type
cleaning cassette is not recommended.
After you clean the player, press and hold the eject
button for ve seconds to reset the CLEAN indicator.
The radio will display --- or CLEANED to show the
indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Care of Your CDs and DVDs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust. If the surface of a disc is soiled, dampen
a clean, soft cloth in a mild, neutral detergent solution
and clean it, wiping from the center to the edge.
Be sure never to touch the side without writing when
handling discs. Pick up discs by grasping the outer
edges or the edge of the hole and the outer edge.
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Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-47.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a 10-second chime. The lights
and chime will come on each time the ignition is turned
on until the problem is repaired. See your dealer for
service.Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here’s what
happens with ABS:
A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
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The traction off light will come on under the following
conditions:
The Traction Assist System is turned off, either by
pressing the TAS on/off button or turning off the
automatic engagement feature of the TAS.
The transmission is in FIRST (1); TAS will not
operate in this gear. This is normal.
The vehicle is driven on an extremely rough road.
When the vehicle leaves the rough surface, slows
down or stops, the light will go off and TAS will
be on again. This is normal.
A Traction Assist System, Anti-Lock Brake System
or engine-related problem has been detected and
the vehicle needs service.
If the vehicle has been driven with the TAS system
on for long periods of time, or if the vehicle has
gone through many high speed braking maneuvers
the system may be automatically disabled. The
system will automatically re-enable after
approximately two minutes of not using the brakes.
SeeTraction Off Light on page 3-48.The Traction Assist System, as delivered from the
factory, will automatically come on whenever you start
your vehicle. To limit wheel spin, especially in
slippery road conditions, you should always leave the
system on. But you can turn the TAS off if you ever need
to. You should turn the TAS off if your vehicle ever
gets stuck in sand, mud or snow and rocking the vehicle
is required. See “Rocking Your Vehicle” underIf You
Are Stuck: In Sand, Mud, Ice or Snow on page 4-50.
To turn the system on or
off, press the TAS on/off
button located on the
instrument panel.
If you used the button to turn the system off, the traction
off light will come on and stay on. You can turn the
system back on at any time by pressing the button
again. The traction off light should go off.
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If desired, you can change the TAS automatic
engagement feature so that the system will not come on
automatically when the engine is started. To do so:
1. Park the vehicle with the ignition off and the
transmission in PARK (P).
2. Turn the ignition to RUN; do not start the engine.
3. Apply the brake pedal, shift into NEUTRAL (N),
press the accelerator pedal to the oor and then
press the TAS on/off button and hold it down for at
least six seconds.
4. Release the TAS button and both pedals.
5. Turn off the ignition and wait a few seconds.
The next time you start your vehicle, the TAS will not
automatically come on. You can restore the automatic
feature by using the same procedure. Whether the TAS is
set to come on automatically or not, you can always turn
the system on or off by pressing the TAS on/off button.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
Stabilitrak®System
Your vehicle may be equipped with the
Stabilitrak®system which combines antilock brake,
traction and stability control systems and helps the driver
maintain directional control of the vehicle in most
driving conditions.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
ensure there are no problems. You may hear or feel
the system working. This is normal and does not mean
there is a problem with your vehicle. The system
should initialize before the vehicle reaches 20 m.p.h.
(32 km/h). In some cases, it may take approximately two
miles of driving before the system initializes.
If the system fails to turn on or activate, the STABILITY
SYS DISABLED or SERVICE STABILITY message
will be displayed. If the vehicle has gone through heavy
acceleration or braking during the rst two miles after
starting your vehicle, the STABILITY SYS DISABLED
message may appear. If this is the case, your
vehicle does not need servicing. Turn your vehicle off
and back on again to reset the system. If either message
appears on the Driver Information Center (DIC), and
your vehicle hasn’t gone through hard acceleration
or braking in the rst two miles, your vehicle should be
taken in for service.
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The traction control system is enabled automatically
when you start your vehicle, and it will activate and
display the TRACTION ACTIVE message in the Driver
Information Center (DIC) if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If you turn off Stabilitrak
®, only the brake-traction
control portion of traction control will work. The engine
speed management will be disabled. In this state, engine
power is not reduced automatically and the driven wheels
can spin more freely. This can cause the brake-traction
control to activate constantly. For more information on the
traction active message, seeDriver Information
Center (DIC) on page 3-58.
Notice:If the traction off light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not
allow the wheel(s) of one axle to spin excessively.
If you do, you may be causing damage to the
transfer case. This could lead to costly repairs not
covered by your warranty.
If the brake-traction control system activates constantly or
if the brakes have heated up due to high speed braking,
the brake-traction control will be disabled and the
TRACTION SYS LIMITED message will be displayed. In
the limited mode, the traction control system will only use
engine traction-control and is limited in its ability to
provide optimal performance since the system will not
utilize brake traction-control to control slip on the drivewheels. The system will return to normal operation after
the brakes have cooled. This can take up to two minutes
or longer depending on brake usage.
Notice:If you allow the wheel(s) of one axle to spin
excessively while the traction off, ABS and brake
warning lights and the SERVICE STABILITY
MESSAGE are displayed, you could damage the
transfer case. The repairs would not be covered by
your warranty. Reduce engine power and do not
spin the wheel(s) excessively while these lights and
this message are displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear a noise
or vibration. This is normal.
If your vehicle is in cruise control when the system
activates, the STABILITY SYS ACTIVE message will
appear on the Driver Information Center (DIC), and the
cruise control will automatically disengage. When
road conditions allow you to use cruise again, you may
re-engage the cruise control. See “Cruise Control”
underTurn Signal/Multifunction Lever on page 3-8
Stabilitrak
®may also turn off automatically if it
determines that a problem exists with the system. If the
problem does not clear itself after restarting the
vehicle, you should see your dealer for service.
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To reinstall the lower air dam do the following:
1. Line up each push-pin
with its intended
retainer and push the
washer portion of
the push-pin towards
the retainer until it locks
into place.
2. Push the at end of the
push-pin towards the
retainer until it
locks into place,
making sure each is
secure.Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields (if so equipped) are properly
attached. Be sure you read all the information about
your four-wheel-drive or all-wheel-drive vehicle in
this manual. Is there enough fuel? Is the spare tire fully
inated? Are the uid levels up where they should
be? What are the local laws that apply to off-roading
where you will be driving? If you do not know, you
should check with law enforcement people in the area.
Will you be on someone’s private land? If so, be
sure to get the necessary permission.
Loading Your Vehicle for Off-Road
Driving
There are some important things to remember about
how to load your vehicle.
The heaviest things should be on the load oor and
forward of your rear axle. Put heavier items as far
forward as you can.
Be sure the load is secured properly, so driving on
the off-road terrain does not toss things around.
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After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired — by alcohol or drugs, with night vision
problems, or by fatigue.
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