service GMC YUKON 2003 User Guide

Ignition Positions
With the key in the ignition switch, you can turn the key
to four different positions.
A (LOCK):This position locks your ignition and
transmission. It’s a theft-deterrent feature. You will only
be able to remove your key when the ignition is
turned to LOCK.
B (ACCESSORY):This position lets you use things like
the radio, power windows and the windshield wipers
when the engine is off.Notice:If your key seems stuck in LOCK and you
can’t turn it, be sure you are using the correct key;
if so, is it all the way in? Turn the key only with
your hand. Using a tool to force it could break the
key or the ignition switch. If none of these works,
then your vehicle needs service.
C (RUN):This is the position for driving.
D (START):This position starts your engine.
Retained Accessory Power (RAP)
Your vehicle may be equipped with a Retained
Accessory Power (RAP) feature which will allow certain
features on your vehicle to continue to work up to
10 minutes after the ignition key is turned to OFF.
Your radio, power windows, sunroof (if equipped), and
OnStar
®System (if equipped) will work when the ignition
key is in RUN or ACCESSORY. Once the key is
turned from RUN to LOCK, these features will continue
to work for up to 10 minutes or until a door is opened.
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g(4LO):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 4LO if you are driving off-road in
deep sand, deep mud, deep snow and climbing
or descending steep hills.
{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. See″Parking Brake″in the
Index.
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 message″underDriver Information Center (DIC)
on page 3-53.
Shifting into 4HI or AUTO 4WD
Press and release the 4 hi or AUTO 4WD switch. This
can be done at any speed (except when shifting
from 4LO), and the indicator light willash while shifting.
It will remain illuminated when the shift is completed.
Shifting into 2HI
Press and release the 2 hi switch. This can be done at
any speed (except when shifting from 4LO).
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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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To change the preselected tilt position, adjust the
mirrors to the desired position while the vehicle is in
REVERSE (R). When the vehicle is shifted out of
REVERSE (R), this new position is saved in memory as
the tilt position.
You may be able to enabled/disable this feature through
the Driver Information Center. SeeDriver Information
Center (DIC) on page 3-53.
Outside Convex Mirror
Your passenger’s side mirror is convex. A convex
mirror’s surface is curved so you can see more from the
driver’s seat.
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
Outside Heated Mirrors
The outside rearview mirrors with this option have a
defrost mode.
To turn on the defrost feature, press the rear window
defogger button. See“Rear Window Defogger”
underDual Automatic Climate Control System on
page 3-26for further information.
OnStar®System
OnStar®uses global positioning system (GPS) satellite
technology, wireless communications, and state of
the art call centers to provide you with a wide range of
safety, security, information and convenience services.
An OnStar
®subscription plan is included in the price
of your vehicle. You can easily upgrade or extend your
OnStar
®services to meet your personal needs.
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A complete OnStar®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in your OnStar®-equipped
vehicle’s glove box literature. For more information, visit
www.onstar.com, contact OnStar
®at 1−888−4−ONSTAR
(1−888−466−7827), or press the blue OnStar®button to
speak to an OnStar®advisor 24 hours a day, 7 days
a week.
OnStar®Services
OnStar®provides a number of service plans to closely
meet your needs. Some of the services currently
provided by OnStar
®are:
Automatic Notication of Air Bag Deployment
Emergency Services
Roadside Assistance Stolen Vehicle Tracking
AccidentAssist
Remote Door Unlock
Remote Diagnostics
Online and Personal Concierge Services
Route Support
RideAssist
Information and Convenience Services
OnStar®Personal Calling
With OnStar®Personal Calling, you have a safer way to
stay connected while driving. It’s a hands-free wireless
phone that’s integrated into your vehicle. You can place
calls nationwide using voice-activated dialing with no
contracts, no roaming charges and no access fees. To
nd out more about OnStar
®Personal Calling, refer
to the OnStar®owner’s guide in your vehicle’s glove
box, or call OnStar®at 1−888−4−ONSTAR
(1−888−466−7827).
OnStar®Virtual Advisor
With OnStar®Virtual Advisor you can listen to your
favorite news, entertainment and information topics,
such as traffic and weather reports, stock quotes
and sports scores. You listen to your e-mail through
your vehicle’s speakers, and reply with your hands on
the wheel and your eyes on the road.
A completed Subscription Service Agreement is required
prior to delivery of OnStar
®services and prepaid
calling minutes are also required for OnStar®Personal
Calling and OnStar®Virtual Advisor use. Terms and
conditions of the Subscription Service Agreement can be
found at www.onstar.com.
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This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
(1) this device may not cause interference, and (2) this
device must accept any interference, including
interference that may cause undesired operation of the
device.
Changes and modications to this system by other than
an authorized service facility could void authorization
to use this equipment.
Programming the HomeLink®
Transmitter
Do not use the HomeLink®Transmitter with any garage
door opener that does not have the“stop and reverse”
feature. This includes any garage door opener model
manufactured before April 1, 1982. If you have a newer
garage door opener with rolling codes, please be
sure to follow steps 6 through 8 to complete the
programming of your HomeLink
®Transmitter.
Read the instructions completely before attempting to
program the HomeLink
®Transmitter. Because of
the steps involved, it may be helpful to have another
person available to assist you in programming the
transmitter.Keep the original transmitter for use in other vehicles as
well as for future HomeLink
®programming. It is also
recommended that upon the sale of the vehicle,
the programmed HomeLink
®buttons should be erased
for security purposes. Refer to“Erasing HomeLink®
Buttons”or, for assistance, contact HomeLink®on the
internet at: www.homelink.com or by calling
1-800-355-3515.
Be sure that people and objects are clear of the garage
door or gate operator you are programming. When
programming a garage door, it is advised to park outside
of the garage.
It is recommended that a new battery be installed in
your hand-held transmitter for quicker and more
accurate transmission of the radio frequency.
Your vehicle’s engine should be turned off while
programming the transmitter. Follow these steps to
program up to three channels:
1. Press and hold down the two outside buttons,
releasing only when the indicator light begins to
ash, after 20 seconds. Do not hold down the
buttons for longer than 30 seconds and do not
repeat this step to program a second and/or
third transmitter to the remaining two HomeLink
®
buttons.
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When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps or the last
chosen headlamp setting that was used.
When you turn the headlamp switch off, the headlamps
will go off, and your DRL lamps will illuminate,
provided it is not dark outside.
Shifting the transmission into PARK (P) will allow you to
idle the vehicle with the DRL off. The DRL will stay
off until you shift the transmission out of PARK (P).
This procedure applies only to vehiclesfirst sold in the
United States.
Fog Lamps
If your vehicle has fog lamps, use them for better vision
in foggy or misty conditions.
The fog lamp button is
located on the left side of
the instrument panel.Your parking lamps and/or low-beam headlamps must
be on for your fog lamps to work.
Press the button to turn the fog lamps on. Press the
button again to turn them off. An indicator light will glow
in the button when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps
in the dark without turning on your headlamps.
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after you
restart the vehicle, you will need to press the fog
lamp button again.
Auxiliary Roof Mounted Lamp Switch
If your vehicle has this feature, this switch includes
wiring provisions for a dealer or a qualified service
center to install an auxiliary roof lamp.
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The safety belt light will
also come on and stay on
for several seconds, then it
willflash for several more.
If the driver’s belt is already buckled, neither the chime
nor the light will come on.
Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel cluster, which shows the air bag symbol.
The system checks the air bag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the air bag
sensors, the air bag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
air bag system, seeAir Bag Systems on page 1-70.This light will come on
when you start your
vehicle, and it willflash for
a few seconds. Then
the light should go out.
This means the system is
ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
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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 air bag readiness
light ever come on together, it means that
something may be wrong with the air bag
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 air
bag. See“Air Bag Readiness Light”in the
Index.
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.
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Voltmeter Gage
When your engine is not running, but the ignition is in
RUN, this gage shows your battery’s state of charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Brake System Warning Light
With the ignition on, the brake system warning light will
flash when you set the parking brake. The light willflash if
the parking brake doesn’t release fully. If you try to drive
with the parking brake engaged, a chime will sound when
the vehicle speed is greater than 3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided into two
parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
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