
AUTO (Automatic):Turning the control to this position
puts the system into automatic headlamp mode. An
indicator light will illuminate when this position is
selected.
;(Parking Lamps):Turning the control to this
position turns on the parking lamps, together with the
following:
•Sidemarker Lamps
•Taillamps
•License Plate Lamps
•Instrument Panel Lights
•Roof Marker Lamps (If Equipped)
5(Headlamps):Turning the control to this position
turns on the headlamps, together with the previously
listed lamps and lights.
You can switch your headlamps from high to low-beam
by pushing the turn signal/high-beam lever towards
the instrument panel.
A circuit breaker protects your headlamps. If you have
an electrical overload, your headlamps willflicker on and
off. Have your headlamp wiring checked right away if
this happens.
Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as
the taillamps, sidemarker, parking lamps and the
instrument panel lights. The radio lights will also be dim.
Your vehicle is equipped with a light sensor located
on the top of the instrument panel in the defroster grille.
Be sure it is not covered, or the system will be on
whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor sees a change in lighting lasting
longer than the delay.
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2003 - Yukon/Yukon XL

This switch is located on
the center of the
instrument panel near the
comfort controls.
When the switch wiring is connected to an auxiliary roof
mounted lamp, pressing the switch will activate the lamp
and illuminate an indicator light near the switch. Pressing
the switch again will turn off the roof mounted lamp.
Interior Lamps
Instrument Panel Brightness
D
: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.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lights will
not come on if the dome override button is pressed in.
Entry Lighting
Your vehicle is equipped with an illuminated entry
feature.
When the doors are opened, the dome lamps will come
on if the dome override button is in the out position.
If the dome override button is pressed in, the lamps will
not come on.
3-18
2003 - Yukon/Yukon XL

Warning Lights, Gages and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly–and even
dangerous. So please get to know your warning lights
and gages. They’re a big help.
Your vehicle also has a driver information system that
works along with the warning lights and gages. See
Driver Information Center (DIC) on page 3-53.
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2003 - Yukon/Yukon XL

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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2003 - Yukon/Yukon XL

If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on thefirst occurrence of
a problem and each time the vehicle is shut off and then
restarted. SeeBrake System Warning Light on
page 3-43.
Traction Off Light
If you have the Traction
Assist System, this light
should come on briefly
when you turn the ignition
to RUN.
If the light doesn’t come on then, the system may
require service; have itfixed so it will be there to warn
you if the system is turned off.If the light stays on, or comes on when you’re driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
The traction off light may come on for the following
reasons:
•If you turn the system off by pressing the TAS
on/off button located to the left of the steering wheel,
the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.
•If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation. To
turn the system back on, move the shift lever
back to a position other than FIRST (1); the light
should go off. SeeTraction Assist System (TAS) on
page 4-10.
•The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, seeTraction Assist
System (TAS) on page 4-10.
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2003 - Yukon/Yukon XL

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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2003 - Yukon/Yukon XL

with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.If there’s a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-44.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there’s a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a 10-second chime. The lights
and chime will come on each time the ignition is turned
on until the problem is repaired. See your dealer for
service.
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2003 - Yukon/Yukon XL

If the brake-traction control system activates constantly
or if the brakes have heated up due to high speed
braking, the brake-traction control will be automatically
disabled. The system will come back on after the
brakes have cooled. This can take up to two minutes or
longer depending on brake usage.
Notice:Don’t allow the wheel(s) of one axle to spin
excessively when the traction off, ABS and brake
lights are on and the SERVICE STABILITY MESSAGE
is displayed. In this situation, damage to the
transfer case is possible. This could lead to costly
repairs not covered by your warranty. You should
immediately reduce engine power until the lights
and messages are no longer displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear a noise
or vibration. This is normal.
If your vehicle is in cruise control when the system
activates, the STABILITY SYS ACTIVE message will
appear on the Driver Information Center and the cruise
control will automatically disengage. When road
conditions allow you to use cruise again, you may
re-engage the cruise control. See“Cruise Control”under
Turn Signal/Multifunction Lever on page 3-8Stabilitrak®may also turn off automatically if it
determines that a problem exists with the system. If the
problem does not clear itself after restarting the
vehicle, you should see your dealer for service.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the“driver lost control”accidents mentioned on
the news happen on curves. Here’s why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves.
The traction of the tires against the road surface makes
it possible for the vehicle to change its path when
you turn the front wheels. If there’s no traction, inertia
will keep the vehicle going in the same direction. If
you’ve ever tried to steer a vehicle on wet ice, you’ll
understand this.
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2003 - Yukon/Yukon XL