2005 GMC YUKON XL service

Passlock®
Your vehicle is equipped with the Passlock®
theft-deterrent system.
Passlock®is a passive theft-deterrent system. Passlock®
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
®system is not working
properly and must be serviced by your dealer. Your
vehicle is not protected by Passlock
®at this time. You
may also want to check the fuse. SeeFuses and Circuit
Breakers on page 5-105. See your dealer for service.
In an emergency, call the Roadside Assistance Center.
SeeRoadside Assistance Program on page 7-6.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. 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 — fast or
slow — 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 4-52for more information.
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Ignition Positions
Use the key to turn the ignition switch to four different
positions.
A (Lock):This position locks the ignition and
transmission. It is a theft-deterrent feature. You will only
be able to remove the key when the ignition is turned
to LOCK.Notice:Using a tool to force the key from the
ignition switch could cause damage or break the
key. Use the correct key and turn the key only with
your hand. Make sure the key is in all the way. If
none of this works, then your vehicle needs service.
B (Accessory):This position lets you use things like
the radio and the windshield wipers when the engine
is off.
Notice:Lengthy operation of features such as the
radio in the accessory ignition position may drain the
battery and prevent your vehicle from starting. Do not
operate your vehicle in the accessory ignition
position for a long period of time.
C (Run):This is the position for driving.
D (Start):This position starts the engine.
Retained Accessory Power (RAP)
The Retained Accessory Power (RAP) feature will allow
certain features on your vehicle to continue to work
for up to 10 minutes after the ignition key is turned to
LOCK or until one of the doors is opened.
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Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.
Control buttons for the OnStar
®system are at the bottom
of the mirror. SeeOnStar®System on page 2-37for more
information about the services OnStar®provides.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, briey to
turn the compass/temperature display on or off.
If the display reads CAL, the compass needs to be
calibrated. For more information, see “Compass
Calibration” following.To adjust between Fahrenheit and Celsius, do the
following:
1. Press and hold the on/off button for approximately
four seconds until either a ashing F or C appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will return.
If an abnormal temperature reading is displayed for an
extended period of time, please see your GM dealer.
Under certain circumstances, a delay in updating
the temperature is normal.
Automatic Dimming Mirror Operation
The automatic dimming mirror function is turned
on automatically each time the ignition is started. To
operate the automatic dimming mirror, do the following:
1. Make sure the green indicator light, located to the left
of the on/off button, is lit. If it is not, press and hold
the on/off button for approximately six seconds until
the green light comes on, indicating that the mirror is
in automatic dimming mode.
2. Turn off the automatic dimming mirror function by
pressing and holding the on/off button for
approximately six seconds, until the green indicator
light turns off.
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OnStar®System
OnStar®uses global positioning system (GPS) satellite
technology, wireless communications, and call centers
to provide you with a wide range of safety, security,
information, and convenience services.
A complete OnStar
®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in the vehicle’s glove box
literature. For more information, visit www.onstar.com or
www.onstarcanada.com. Contact OnStar
®at
1-888-4-ONSTAR (1-888-466-7827), or press the
OnStar
®button to speak to an OnStar®advisor 24 hours
a day, 7 days a week.
Terms and conditions of the Subscription Service
Agreement can be found at www.onstar.com or
www.onstarcanada.com.
OnStar®Services
For new vehicles equipped with OnStar®, the Safe and
Sound Plan is included for the rst year. You can
extend this plan beyond the rst year, or upgrade to the
Directions and Connections Plan to meet your needs.
For more information, press the OnStar
®button to speak
to an advisor.
Safe and Sound Plan

Automatic Notication of Airbag Deployment
Emergency Services
Roadside Assistance
Stolen Vehicle Tracking
AccidentAssist
Remote Door Unlock/Vehicle Alert
Remote Diagnostics
Information and Convenience Services
Online Concierge
Directions and Connections Plan
All Safe and Sound Plan Services
Driving Directions
RideAssist
Information and Convenience Services
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HomeLink®Transmitter
HomeLink®a combined universal transmitter and
receiver, provides a way to replace up to three
hand-held transmitters used to activate devices such as
gate operators, garage door openers, entry door
locks, security systems and home lighting. Additional
HomeLink
®information can be found on the Internet at
www.homelink.com or by calling 1-800-355-3515.
If your vehicle is equipped with the HomeLink
®
Transmitter, it complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired
operation.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.
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Airbag Readiness Light
There is an airbag readiness light on the instrument
panel, 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 wiring and the crash sensing and
diagnostic module. For more information on the
airbag system, seeAirbag System on page 1-70.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. Then the
light should go out. 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.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the airbag readiness light
stays on after you start your vehicle.
The airbag readiness light should ash for a few
seconds when you turn the ignition key to RUN. If the
light doesn’t come on then, have it xed so it will
be ready to warn you if there is a problem.
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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 1-79
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 3-31.
Charging System Light
The charging system light
will come on briey when
you turn on the ignition,
but the engine is not
running, as a check to
show you it is working.
It should go out once the engine is running. If it stays on,
or comes on while you are driving, you may have a
problem with the charging system. It could indicate that
you have problems with a generator drive belt, or another
electrical problem. Have it checked right away. Driving
while this light is on could drain your battery.
When this light comes on the DIC will also display the
battery not charging message. SeeDIC Warnings
and Messages on page 3-50.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and 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. The gage may
transition from a higher to lower or a lower to higher
reading, this is normal. 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
ash when you set the parking brake. The light will ash 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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