
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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2003 - Yukon/Yukon XL

Oil Pressure Gage
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in kPa
(kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem
causing low oil pressure. Check your oil as soon as
possible. SeeOil Pressure LowunderDIC Warnings
and Messages on page 3-64andEngine Oil on
page 5-16.
{CAUTION:
Don’t keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty. United States
Canada
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2003 - Yukon/Yukon XL

C (Personalization):This button will change personal
options available on your vehicle.
D (Select):This button resets certain functions and
turns off or acknowledges messages on the DIC.
If your vehicle is not equipped with the DIC steering
wheel buttons you will not have all of the features listed
above, and you will turn off, or acknowledge DIC
messages by using the trip odometer reset stem located
on the instrument panel cluster.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver and the
information that was last displayed before the engine
was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing the select button will
acknowledge any current warning or service messages.
The DIC has different modes which can be accessed
by pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization
and select. The button functions are detailed in
the following.If your vehicle is not equipped with the DIC steering
wheel buttons not all of the features listed will be
available on your vehicle.
Trip Information Button
Use the trip information button to scroll through the
ODOMETER, PERSONAL TRIP ON/OFF, BUSINESS
TRIP ON/OFF, HOURMETER, ANNUAL LOG and
TIMER. If the personal trip and/or the business trip are
set to ON, you will also be able to scroll through
more messages. SeePersonal TripandBusiness Trip
next for more information.
If your vehicle is not equipped with the DIC steering
wheel buttons you can select the trip information
by pressing the trip odometer reset stem on the
instrument panel cluster.
Personal Trip
If the PERSONAL TRIP is on (turn it on or off by
pressing the select button) you will also be able to scroll
through the following:
•PERSONAL: XX MI—This shows the current
distance traveled since the last reset for the
personal trip odometer in either miles or kilometers.
•PERSONAL: XX.X GAL—This shows the amount
of fuel used for the personal trip.
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2003 - Yukon/Yukon XL

ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-29for further
information.
BATTERY NOT CHARGING
If the battery is not charging during operation, this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the
select button will acknowledge this message and clear it
from the DIC display.
SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the DIC. Have a qualified
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
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2003 - Yukon/Yukon XL

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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2003 - Yukon/Yukon XL

SERVICE 4 WHEEL STEER
If a problem occurs with the 4 wheel steer system, this
message will appear on the DIC. If this message
appears, stop as soon as possible, and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the four wheel
steer system needs service.
SERVICE 4WD
If a problem occurs with the four wheel drive system
this message will appear on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the four wheel
drive system needs service.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If this message
appears turn off the vehicle. Restart the vehicle and
check for the message on the DIC display. If the
message is still displayed, or appears again when you
begin driving, the ride control needs service.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will
hear a chime. Move the turn signal/multifunction lever to
the off position. Pressing the select button will
acknowledge this message and clear it from the DIC
display.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, this
message will appear on the DIC display and you
will hear a chime. Turn the vehicle off and check the
liftgate. Restart the vehicle and check for the message
on the DIC display. Pressing the select button will
acknowledge this message and clear it from the DIC
display.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing the select button will acknowledge
this message and clear it from the DIC display.
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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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To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the time display. Then press
and hold AUDIO for more than two seconds until you
hear a beep. CEN will appear on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release AUDIO until
BAL appears on the display. Then press and hold the up
or the down arrow to move the sound toward the right
or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD appears
on the display. Then press and hold the up or the
down arrow to move the sound toward the front or the
rear speakers.
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L and a zero
or F and a zero will appear on the display.To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the time display. Then press
and hold AUDIO for more than two seconds until you
hear a beep. CEN will appear on the display.
Fade may not be available if you have a regular cab
model.Radio Messages
CAL (Calibrated):Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been configured properly for your vehicle and must
be returned to the dealership for service.
LOC (Locked):This message is displayed when the
Theftlock
®system has locked up. Your vehicle must be
returned to the dealership for service.
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