light GMC YUKON 2003 Repair Manual

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light doesn’t come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
•Light Flashing—Amisfire condition has been
detected. A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
•Light On Steady—An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
•Reducing vehicle speed.
•Avoiding hard accelerations.
•Avoiding steep uphill grades.
•If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stopsflashing and remains on steady, see“If
the Light Is On Steady”following.
If the light continues toflash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see“If
the Light Is On Steady”following. If the light is still
flashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misfiring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has the
proper test equipment and diagnostic tools tofix any
mechanical or electrical problems that may have
developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the Check
Engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
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Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See“Cruise
Control”underTurn
Signal/Multifunction Lever
on page 3-8.
Tow/Haul Mode Light
This light is displayed
when the tow/haul mode
has been activated.
For more information, seeTowing a Trailer on
page 4-61.
Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage willfirst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
When the fuel tank is low the FUEL LEVEL LOW
message will appear. SeeDriver Information Center
(DIC) on page 3-53.
United StatesCanada
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Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
•At the gas station, the fuel pump shuts off before
the gage reads full.
•It takes a little more or less fuel tofill up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity tofill the tank.
•The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briefly when
you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. SeeFuel on
page 5-4.
Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features.
A (Trip Information):This button will display the
odometer, personal trip odometer, business trip
odometer, hourmeter, annual log and the timer.
B (Fuel Information):This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.
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If your vehicle is not equipped with the DIC steering
wheel buttons you will not have any of these
personalization options except for DISPLAY
LANGUAGE. See DISPLAY LANGUAGE later in this
section for more information.
•AUTOMATIC LOCKING
•AUTOMATIC UNLOCKING
•REMOTE LOCK FEEDBACK
•ALARM WARNING TYPE
•REMOTE UNLOCK FEEDBACK
•HEADLAMPS ON AT EXIT
•PERIMETER LIGHTING
•SEAT POSITION RECALL
•EASY EXIT DRIVER SEAT
•CURB VIEW ASSIST
•DISPLAY LANGUAGE
•DISPLAY UNITS (ENG/MET)
The default options for the above features were set
when your vehicle left the factory. The default options
are noted in the text following, but may have been
changed from their default state since then. The driver’s
preferences are recalled by pressing the unlock
button on the remote keyless entry transmitter or by
pressing the appropriate memory button 1 or 2 located
on the driver’s door.
Alarm Warning Type
Press the personalization button until ALARM
WARNING TYPE appears in the display. To select your
personalization for alarm warning type, press the
select button while ALARM WARNING TYPE is
displayed on the DIC. Pressing the select button will
scroll through the following choices:
ALARM WARNING: BOTH (default):The headlamps
willflash and the horn will chirp when the alarm is
active.
ALARM WARNING: OFF:There will be no alarm
warning on activation.
ALARM WARNING: HORN:The horn will chirp when
the alarm is active.
ALARM WARNING: LAMPS:The headlamps willflash
when the alarm is active.
Choose one of the four options and press the
personalization button while it is displayed on the DIC to
select it and move on to the next feature. For more
information on alarm warning type, seeContent
Theft-Deterrent on page 2-16.
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Seat Position Recall
Press the personalization button until SEAT POSITION
RECALL appears on the display. To select your
personalization for seat position recall, press the select
button while SEAT POSITION RECALL is displayed
on the DIC. Pressing the select button will scroll through
the following choices:
SEAT POSITION RECALL OFF (default):The memory
seat position you saved will only be recalled when the
memory button 1 or 2 is pressed on the driver’s
door panel.
SEAT POSITION RECALL AT KEY IN:The memory
seat position you saved will be recalled when you
put the key in the ignition.
SEAT POSITION RECALL ON REMOTE:The memory
seat position you saved will be recalled when you
unlock the vehicle with the remote keyless entry
transmitter.
Choose one of the three options and press the
personalization button while it is displayed on the DIC to
select it and move on to the next feature. For more
information on seat position recall seeMemory Seat on
page 2-58.
Perimeter Lighting
Press the personalization button until PERIMETER
LIGHTING appears in the display. To select your
personalization for perimeter lighting, press the select
button while PERIMETER LIGHTING is displayed on the
DIC. Pressing the select button will scroll through the
following choices:
PERIMETER LIGHTING ON (default):The headlamps
and back-up lamps will come on for 40 seconds, if it
is dark enough outside, when you unlock the vehicle
with the remote keyless entry transmitter.
PERIMETER LIGHTING OFF:The perimeter lights will
not come on when you unlock the vehicle with the
remote keyless entry transmitter.
Choose on of the two options and press the
personalization button while it is displayed on the DIC to
select it and move on to the next feature.
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SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
SeeBrake System Warning Light on page 3-43.{CAUTION:
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service.
See“Brake System Warning Light”in the
Index.
If the brake system warning light isn’t on, you
still have brakes, but the supplemental brake
assist system may not operate properly. In the
event of a vacuum loss, you may not have
vacuum power assist for braking. The brake
pedal will be harder to push and it will take
longer to stop. If you continue to drive with
this message displayed it can lead to a crash.
Have the brake system serviced as soon as
possible.
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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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Playing a Compact Disc
If playing a CD-R the sound quality may be reduced
due to CD-R quality, the method of recording, the quality
of the music that has been recorded and the way the
CD-R has been handled. You may experience an
increase in skipping, difficulty infinding tracks and/or
difficulty in loading and ejecting. If these problems occur
try a known good CD.
Do not add paper labels to discs, they could get caught
in the CD player.
Do not play 3 inch discs without a standard adapter disc.
If an error appears on the display, see“Compact Disc
Messages”later in this section.
LOAD CD
Z:Press the LOAD side of this button to
load CDs into the compact disc player. This compact
disc player will hold up to six discs.
To insert one disc, do the following:
1. Turn the ignition on.
2. Press and release the LOAD side of the LOAD CD
button.
3. Wait for the light, located to the right of the slot, to
turn green.
4. Load a disc. Insert the disc partway into the slot,
label side up. The player will pull the disc in.When a disc is inserted, the CD symbol will be
displayed. If you select an equalization setting for your
disc, it will be activated each time you play a disc.
If the radio is on or off, the disc will begin to play
automatically.
To insert multiple discs, do the following:
1. Turn the ignition on.
2. Press and hold the LOAD side of the LOAD CD
button for two seconds.
You will hear a beep and the light, located to the
right of the slot, will begin toflash.
3. Once the light stopsflashing and turns green, load
a disc. Insert the disc partway into the slot, label
side up. The player will pull the disc in.
Once the disc is loaded, the light will beginflashing
again. Once the light stopsflashing and turns
green you can load another disc. The disc player
takes up to six discs. Do not try to load more
than six.
To load more than one disc but less than six, complete
Steps 1 through 3. When you havefinished loading
discs, with the radio on or off, press the LOAD side of
the LOAD CD button to cancel the loading function. The
radio will begin to play the last CD loaded.
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