2003 GMC YUKON service stability

NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-55orTowing
Your Vehicle on page 4-54for more information.
Indicator lights in the switches show which setting you
are in. The indicator lights will come on briey 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 willash 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.
If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See
SERVICE 4WD underDriver Information Center (DIC)
on page 3-53.
Shifting into 4LO
To shift to the 4LO position, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (4.8 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4LO switch. You must wait for the
4LO indicator light to stopashing and remain
illuminated before shifting your transmission in gear.Notice:Shifting the transmission into gear before
the 4LO indicator light has stoppedflashing could
damage the transfer case. To help avoid damaging
your vehicle, always wait for the 4LO indicator light
to stopflashing before shifting your transmission
into gear.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light willash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will return to the setting last chosen.
When in 4LO, the vehicle stability is disabled. For more
information seeStabilitrak
®System on page 4-12.
Shifting Out of 4LO
To shift from 4LO to AWD your vehicle must be stopped
or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N) and the ignition in RUN.
The preferred method for shifting out of 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the AWD switch. You must wait for the AWD
indicator light to stopashing and remain illuminated
before shifting your transmission into gear.
If the AWD switch is pressed when your vehicle is in
gear and/or moving, the AWD indicator light willash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).
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2003 - Yukon/Yukon XL

SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your
Stabilitrak
®system. If you see this message try to reset
the system (stop; turn off the engine; then start the engine
again). If the SERVICE STABILITY message still comes
on, it means there is a problem. You should see your
dealer for service. The vehicle is safe to drive, however,
you do not have the benefit of Stabilitrak
®, so reduce your
speed and drive accordingly.
STABILITY SYS ACTIVE
You may see the STABILITY SYS ACTIVE message on
the DIC. It means that an advanced computer-controlled
system has come on to help your vehicle continue to go
in the direction in which you’re steering.
Stabilitrak
®activates when the computer senses that
your vehicle is just starting to spin, as it might if you hit a
patch of ice or other slippery spot on the road. When the
system activates, you may hear a noise or feel a vibration
in the brake pedal. This is normal. When the STABILITY
SYS ACTIVE message is on, you should continue to
steer in the direction you want to go. The system is
designed to help you in bad weather or other difficult
driving situations by making the most of whatever road
conditions will permit.
STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the Stabilitrak®button, or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full benefits of the stability
enhancement system, you should normally leave
Stabilitrak
®on. However, you should turn Stabilitrak®off
if your vehicle gets stuck in sand, mud, ice or snow and
you want to“rock”your vehicle to attempt to free it, or if
you are driving in extreme off-road conditions and require
more wheel spin. SeeIf You Are Stuck: In Sand, Mud, Ice
or Snow on page 4-52. To turn the Stabilitrak
®system
back on press the Stabilitrak®button again. There are
four conditions that can cause this message to appear.
One condition is overheating, which could occur if
Stabilitrak
®activates continuously for an extended period
of time. The message will also be displayed if the brake
system warning light is on. SeeBrake System Warning
Light on page 3-43. The message could be displayed if
the stability system takes longer than usual to complete
its diagnostic checks due to driving conditions. Also, if an
engine or vehicle related problem has been detected, and
the vehicle needs service, the message will appear.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
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2003 - Yukon/Yukon XL

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 is equipped with the Stabilitrak®which
combines antilock brake, traction and stability control
systems and helps the driver maintain directional control
of the vehicle in most driving conditions.
When yourst start your vehicle and begin to drive
away, the system performs several diagnostic checks to
insure 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 therst 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 therst two miles, your vehicle should be
taken in for service.
The STABILITY SYS ACTIVE message will appear on
the Driver Information Center (DIC) only when the
system is both on and activated. You may also feel or
hear the system working; this is normal. For more
information on the stability messages, seeDriver
Information Center (DIC) on page 3-53.
The Stabilitrak
®mode
button is located on the
instrument panel.
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2003 - Yukon/Yukon XL

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 automatically
disabled. The system will come back on after the
brakes have cooled. This can take up to two minutes or
longer depending on brake usage.
Notice:Don’t allow the wheel(s) of one axle to spin
excessively when the traction off, ABS and brake
lights are on and the SERVICE STABILITY MESSAGE
is displayed. In this situation, damage to the
transfer case is possible. This could lead to costly
repairs not covered by your warranty. You should
immediately reduce engine power until the lights
and messages are no longer 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 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”under
Turn Signal/Multifunction Lever on page 3-8Stabilitrak®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.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the“driver lost control”accidents mentioned on
the news happen on curves. Here’s why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves.
The traction of the tires against the road surface makes
it possible for the vehicle to change its path when
you turn the front wheels. If there’s no traction, inertia
will keep the vehicle going in the same direction. If
you’ve ever tried to steer a vehicle on wet ice, you’ll
understand this.
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2003 - Yukon/Yukon XL

SERVICE STABILITY......................................3-70
Setting Preset PTYs (RDS Only).....3-79, 3-89, 3-102
Setting Preset Stations..........3-73, 3-77, 3-87, 3-100
Setting the Time
Radios with Radio Data Systems (RDS).........3-72
Radios without Radio Data Systems (RDS).....3-71
Setting the Tone
(Bass/Treble)....................3-73, 3-78, 3-87, 3-100
Sheet Metal Damage.......................................5-94
Shifting Into Park (P).......................................2-35
Shifting Out of Park (P)...................................2-37
Side Impact Air Bags.......................................1-77
Skidding........................................................4-21
Some Other Rainy Weather Tips.......................4-41
Spare Tire.....................................................5-88
Spare Tire Check............................................6-12
Special Fabric Cleaning Problems.....................5-90
Specifications, Capacities...............................5-106
Speedometer..................................................3-39
Split Bench Seat (50/50)..................................1-11
Split Bench Seat (60/40).................................... 1-9
Stabilitrak
®, All-Wheel Drive..............................2-31
Stabilitrak®System.........................................4-12
STABILITY SYS ACTIVE..................................3-70
STABILITY SYS DISABLED..............................3-70
Stalling on an Incline.......................................4-34
Starter Switch Check
.......................................6-13
Starting Your Engine
.......................................2-20
Steering
........................................................4-14Steering and Suspension Inspection..................6-15
Steering in Emergencies..................................4-15
Steering Tips..................................................4-14
Steering Wheel Controls, Audio.......................3-122
Step-Bumper Pad...........................................4-74
Stereo RCA Jacks.........................................3-117
Storage Areas
Center Console Storage Area........................2-54
Convenience Net.........................................2-56
Cupholder(s)...............................................2-54
Front Storage Area......................................2-54
Glove Box..................................................2-54
Luggage Carrier..........................................2-55
Rear Storage Area.......................................2-56
Storing a Flat or Spare Tire, Jack and Tools.......5-80
Stuck in Sand, Mud, Ice or Snow......................4-52
Sun Visors.....................................................2-15
Sunroof.........................................................2-57
Supplemental Brake Assist System...................... 4-9
T
Tachometer....................................................3-39
Taillamps.......................................................5-57
Temperature and Compass Display....................2-40
Temperature Display........................................2-43
Testing the Alarm............................................2-17
Theft-Deterrent, Radio....................................3-122
Theft-Deterrent Systems...................................2-16
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2003 - Yukon/Yukon XL