2002 GMC YUKON XL key

2-66 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 message center that works along
with warning lights and gages. See ªMessage Centerº in
the Index.
Safety Belt Reminder Light When the key is turned to RUN or START, a chime will
come on for about six seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 20 seconds,
then it will flash for
about 55 seconds.
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, 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 wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, see ªAir Bagº in the Index.
This light will come on
when you start your vehicle,
and it will flash 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.

2-67CAUTION:If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem. Voltmeter
United States Canada
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.

2-68 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
will flash 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, there could be a brake
problem. Have your brake system inspected right away.
United States Canada
This light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then,
have it fixed so it will be ready to warn you if there's
a problem.

2-69If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
CAUTION:Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you've
pulled off the road and stopped carefully, have
the vehicle towed for service. Anti-Lock Brake System Warning Light With the anti
- lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That's normal.
If the light stays on, or comes on when you're driving,
your vehicle needs service. 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. See
ªBrake System Warning Lightº earlier in this section.
The anti
- lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

2-73This 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
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
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 stops flashing and remains on steady, see
ªIf the Light Is On Steadyº following.
If the light continues to flash, 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 ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
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. See ªFilling Your Tankº in the Index. 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.

2-77Here 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 to fill 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 to fill
the tank.

The gage goes back to empty when you turn off
the ignition.
Message Center The message center is located on the left side of the
instrument panel cluster. It gives you important safety
and maintenance facts. When you turn the ignition on,
the entire center lights up for just a few seconds. As
needed, the message center will display one of the
following messages. The message center is capable of
alternating among different messages if needed. Battery If this message 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 message 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 message displayed could drain
your battery.
If you must drive a short distance with this message
displayed, it helps to turn off all your accessories, such
as the radio and the air conditioner.

2-86
You can just let the SIC exit the personalization
mode on its own by waiting approximately
15 seconds without touching any buttons.
The SIC will then display the day/date.

Or you can press the MENU key to move on to
the next programmable feature.
The following is a list of the personal settings that can
be changed:
Automatic Door Lock

Enabled : Doors automatically lock when the vehicle
is shifted out of Park (P).

Disabled : Doors do not lock automatically.
Automatic Door Unlock

Driver : Driver's door unlocks when the vehicle is
shifted into Park (P).

All : All doors unlock when the vehicle is shifted into
Park (P).

Disabled : Doors do not unlock automatically. Remote Lock Feedback

Horn : Horn chirps on second press of the LOCK
button on the keyless entry transmitter.

Lamps : Parking lamps flash on each press of the
LOCK button on the keyless entry transmitter.

Horn and Lamps : Parking lamps flash on each
press, horn chirps on second press of UNLOCK on
the keyless entry transmitter.

None : No horn or lamp feedback to the LOCK
button on the keyless entry transmitter.
Remote Unlock Feedback

Horn : Horn chirps on each press of the UNLOCK
button on the keyless entry transmitter.

Lamps : Parking lamps flash on each press of the
UNLOCK button on the keyless entry transmitter.

Horn and Lamps : Parking lamps flash and horn
chirps on each press of the UNLOCK button on the
keyless entry transmitter.

None : No horn or lamp feedback will occur when
the UNLOCK button on the keyless entry transmitter
is pressed.

2-87Headlamp Delay

None : Headlamps do not stay on after the ignition is
turned to OFF.

10/20/30/60/120/180 Seconds : Amount of
time headlamps stay on after the ignition is turned
to OFF when it is dark (switch must be in auto
headlamp position).
Perimeter Lamps

Enabled : Parking lamps, headlamps and puddle
lamps turn on for 40 seconds with the UNLOCK
button on the keyless entry transmitter. This feature
only operates when it is dark.

Disabled : Feature disabled, no perimeter lamps will
come on. Alarm Warning

Horn : Horn will sound when alarm is active.

Lamps : Headlamps and park lamps will cycle on
and off when alarm is activated.

Horn and Lamps : Horn and lamps will alternate
when the alarm is activated.

None : No alarm warning will come on.
Language

English : All information displayed in English.

French : All information displayed in French.

Spanish : All information displayed in Spanish.

Arabic : All information displayed in Arabic.
Display Units

English : Units displayed in English units.

Metric : Units displayed in metric units.