2002 GMC YUKON warning lights

iv
Vehicle Damage Warnings
Also, in this book you will find these notices:
NOTICE:
These mean there is something that could damage
your vehicle.
In the notice area, we tell you about something that can
damage your vehicle. Many times, this damage would
not be covered by your warranty, and it could be costly.
But the notice will tell you what to do to help avoid
the damage.
When you read other manuals, you might see
CAUTION and NOTICE warnings in different
colors or in different words.
You'll also see warning labels on your vehicle.
They use the same words, CAUTION or NOTICE.
Vehicle Symbols
Your vehicle may be equipped with components and
labels that use symbols instead of text. Symbols,
used on your vehicle, are shown along with the text
describing the operation or information relating to a
specific component, control, message, gage or indicator.
If you need help figuring out a specific name of a
component, gage or indicator reference the following
topics in the Index:

ªEngine Compartment Overviewº

ªInstrument Panelº

ªComfort Controlsº

ªAudio Systemsº
Also see ªWarning Lights and Gagesº in the Index.

2-73 Speedometer and Odometer
Your speedometer lets you see your speed in both miles
per hour (mph) and kilometers per hour (km/h). Your
odometer shows how far your vehicle has been driven,
in either miles (used in the United States) or kilometers
(used in Canada).
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button to toggle between the trip
odometer and the regular odometer. Holding the reset
button for two seconds while the trip odometer is
displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Hour Meter Display
The odometer can also display the number of hours the
engine has run. To display the hour meter, turn the
ignition off, press and hold the reset button for at least
four seconds. The hour meter will be displayed for up
to 30 seconds, or until the ignition is turned on.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
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.

2-74
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
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.

6-31
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.