2006 GMC YUKON XL service indicator

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-8
Safety Belts
.............................................1-26
Child Restraints
.......................................1-47
Airbag System
.........................................1-74
Restraint System Check
............................1-88
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-17
Starting and Operating Your Vehicle
...........2-19
Mirrors
....................................................2-37
OnStar
®System
......................................2-50
Universal Home Remote System
................2-52
Storage Areas
.........................................2-56
Sunroof
..................................................2-61
Vehicle Personalization
.............................2-62
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-22
Warning Lights, Gages, and Indicators
........3-35
Driver Information Center (DIC)
..................3-52
Audio System(s)
.......................................3-74Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-56
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
...............5-10
Rear Axle
...............................................5-46
Four-Wheel Drive
.....................................5-48
Front Axle
...............................................5-49
Bulb Replacement
....................................5-50
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-57
Appearance Care
.....................................5-96
Vehicle Identication
...............................5-105
Electrical System
....................................5-106
Capacities and Specications
...................5-114
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-14
Index................................................................ 1
2006 GMC Yukon, Yukon XL Owner ManualM

In many crashes severe enough to inate an airbag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from
the right front passenger airbag.
Airbags are designed to inate only once. After
an airbag inates, you will need some new parts
for your airbag system. If you do not get them,
the airbag system will not be there to help protect
you in another crash. A new system will include
airbag modules and possibly other parts. The
service manual for your vehicle covers the need
to replace other parts.
Your vehicle is equipped with a crash sensing and
diagnostic module which records information after
a crash. SeeVehicle Data Collection and Event
Data Recorders on page 7-10.
Let only qualied technicians work on your airbag
system. Improper service can mean that an
airbag system will not work properly. See your
dealer for service.
Passenger Sensing System
If your rearview mirror has one of the indicators pictured
in the following illustrations, your vehicle has a passenger
sensing system. The indicator will be visible when you
turn your ignition key to START or RUN. The words ON
and OFF or the symbol for on and off, will be visible on
the rearview mirror during the system check. When the
system check is complete, either the word ON or the
word OFF, or the symbol for on or the symbol for off will
be visible. SeePassenger Airbag Status Indicator on
page 3-38. If your rearview mirror does not have either
of the indicators pictured, then your vehicle does not
have the passenger sensing system.
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
1-82

If a person of adult-size is sitting in the right front
passenger’s seat, but the off indicator is lit, it could be
because that person is not sitting properly in the seat.
If this happens, turn the vehicle off and ask the person to
place the seatback in the fully upright position, then sit
upright in the seat, centered on the seat cushion, with the
person’s legs comfortably extended. Restart the vehicle
and have the person remain in this position for about
two minutes. This will allow the system to detect that
person and then enable the passenger’s airbag.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on,
it means that something may be wrong with
the airbag system. If this ever happens, have
the vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the frontal airbag. SeeAirbag Readiness
Light on page 3-38for more on this, including
important safety information.
1-85

You can choose among four driving settings:
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface traction
conditions are variable. When driving your vehicle in
AUTO 4WD, the front axle is engaged, but the vehicle’s
power is sent only to the rear wheels. When the
vehicle senses a loss of traction, the system will
automatically engage four-wheel drive. Driving in this
mode results in slightly lower fuel economy than
Two-Wheel High.
2
m(Two-Wheel High):This setting is used for driving
in most street and highway situations. Your front axle
is not engaged in two-wheel drive. This setting also
provides the best fuel economy.
4
m(Four-Wheel High):Use the four-wheel high
position when you need extra traction, such as on snowy
or icy roads or in most off-road situations. This setting
also engages your front axle to help drive your vehicle.
This is the best setting to use when plowing snow.
4
n(Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. You may
never need this setting. It sends maximum power to all
four wheels. You might choose Four Wheel-Low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills. StabiliTrak
®
will not engage in this mode. SeeStabiliTrak®System
on page 4-9for more information.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to
set the parking brake before placing the
transfer case in NEUTRAL. SeeParking
Brake on page 2-31.
NEUTRAL (N):Shift the vehicle’s transfer case
to NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-56orTowing
Your Vehicle on page 4-56for more information.
Indicator lights in the button 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 will
ash 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.
2-27

If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See “Service
4WD message” underDIC Warnings and Messages
on page 3-56.
Shifting Into Four-Wheel High or
AUTO 4WD (Automatic Four-Wheel Drive)
Press and release the Four-Wheel High or AUTO
4WD button. This can be done at any speed, except
when shifting from Four-Wheel Low, and the indicator
light will ash while shifting. It will remain on when
the shift is completed.
Shifting Into Two-Wheel High
Press and release the Two-Wheel High button.
This can be done at any speed, except when
shifting from Four-Wheel Low.
Shifting Into Four-Wheel Low
To shift to the Four-Wheel Low position, the ignition
must be in RUN and the vehicle must be stopped
or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred
method for shifting into four-wheel low is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).Press and release the Four-Wheel Low button.
You must wait for the four-wheel low indicator light
to stop ashing and remain on before shifting your
transmission in gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Low indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the Four-Wheel Low indicator light to stop ashing
before shifting the transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges or from
NEUTRAL with the engine running.
If the Four-Wheel Low button is pressed when your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light will ash for 30 seconds and not complete
the shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in NEUTRAL (N).
After 30 seconds the transfer case will shift to
Four-Wheel High mode.
2-28

Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied service
center to install an auxiliary roof lamp.
This button is located on
the center of the instrument
panel near the climate
controls.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate the lamp
and illuminate an indicator light near the button. Pressing
the button again will turn off the roof mounted lamp.
If your vehicle has this button, your vehicle may have the
snow plow prep package. For further information see
Adding a Snow Plow or Similar Equipment on page 4-51.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights.
The thumbwheel for this feature is located next to
the headlamp control.
Turn the thumbwheel up to adjust the instrument panel
lights. Turn the thumbwheel up to return the radio
display to full brightness when the headlamps or parking
lamps are on. To turn on the dome lamps, turn the
thumbwheel all the way up.
Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by turning
the thumbwheel, located next to the exterior lamps
control, all the way up. In this position, the dome lamps
will remain on whether a door is opened or closed.
3-19

Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensors, the airbag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
airbag system, seeAirbag System on page 1-74.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. This means
the system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your airbag
system may not work properly. Have your vehicle
serviced right away.
Passenger Airbag Status Indicator
If your vehicle has a passenger sensing system,
your rearview mirror will have a passenger airbag status
indicator.
When the ignition key is turned to RUN or START,
the passenger airbag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
3-38

If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger’s frontal
airbag. SeePassenger Sensing System on page 1-82
for more on this, including important safety information.
If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there may be
a problem with the lights or the passenger sensing
system. See your dealer for service.
{CAUTION:
If the off indicator and the airbag readiness light
ever come on together, it means that something
may be wrong with the airbag system. If this
ever happens, have the vehicle serviced
promptly, because an adult-size person sitting
in the right front passenger seat may not have
the protection of the frontal airbag. SeeAirbag
Readiness Light on page 3-38.
Battery Warning Light
If this light is displayed
when the engine is
running, you may have
a problem with your
charging system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the light stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories, such
as the radio and the air conditioner.
3-40