2002 GMC YUKON service reset

2-63
OnStar
System (If Equipped)
OnStar is a vehicle communications system that
offers a variety of services and provides a one
-touch
hands
-free communication link between you and the
OnStar Center. To receive OnStar services, a service
subscription agreement is required and an additional
fee may be required. Services are available 24 hours
a day, 7 days a week. For more information,
call 1
-888-ONSTAR-7 (1-888-667-8277).
OnStar Services Button: Press this button once to
contact an advisor who will be able to assist you with
these services. If you are not quickly connected, the
system will automatically reset and redial. This ensures
connection to the center; there is no additional action
required. Press the Communication button to cancel the
automatic redial.
Emergency Button: In an emergency situation,
press the emergency service button. Upon receiving the
call, an advisor at the center will locate your vehicle and
assess the situation. If necessary, the advisor will alert
the nearest emergency service provider.
Communication Button: Press this button at
the end of a call. Also press this button to answer a
call from the center, or cancel a call if one of the other
buttons is accidentally pressed. This button is also
used to access OnStar Personal Calling and Virtual
Advisor services. See the OnStar owner package for
more information.
Volume Control: You can control the volume of the
OnStar System using either the volume knob on the
radio or if equipped, the steering wheel volume controls.
Telltale Light: This light will indicate the status of
the system. A solid green light will come on when you
start the vehicle to let you know that the system is on
and is ready to make or receive calls.
If the light blinks green it means that an incoming or
outgoing call is in progress. Press the Communication
button if you notice the light blinking and you are not
on a call.

2-93 Change Engine Oil
This message is displayed
when the engine oil needs
to be changed. The message
is only displayed for
15 seconds at the start
of each ignition cycle.
When you change the engine oil, be sure to reset the
Engine Oil Life System. See ªEngine Oil, When to
Changeº in the Index.
Security
This message is displayed
when the content
theft
-deterrent system
(if equipped) has been
activated and also monitors
the Passlock

System.
If the security message is displayed continuously while
driving and stays on, there may be a problem with the
Passlock System. Your vehicle will not be protected by
Passlock, and you should contact your GM dealer.
Service 4WD (If Equipped)
If the SERVICE 4WD
message comes on, there
may be a problem with the
automatic transfer case and
service is required.
Malfunctions can be indicated by the system before
any problem is apparent, which may prevent serious
damage to the vehicle. This system is also designed to
assist your service technician in correctly diagnosing
a malfunction.
Low Washer Fluid
This message is displayed
when the vehicle is low on
windshield washer fluid.
The message is only
displayed for 15 seconds
at the start of each
ignition cycle.
For more information, see ªWindshield Washer Fluidº in
the Index.

5-9
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
ªRoadside Assistanceº in the Index. If you want to tow
your vehicle behind another vehicle for recreational
purposes (such as behind a motorhome), see
ªRecreational Vehicle Towingº in the Index.
Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See ªEngine Coolant
Temperature Gageº in the Index. In addition, you will
find a LOW COOLANT, CHECK COOLANT TEMP,
ENGINE OVERHEATED and a REDUCED ENGINE
POWER message in the message center on the
instrument panel. See ªMessage Centerº in the Index.
Overheated Engine Protection Operating
Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates firing groups
of cylinders helps prevent engine damage. In this mode,
you will notice a loss in power and engine performance.
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Driving extended miles
(km) and/or towing a trailer in the overheat protection
mode should be avoided.
NOTICE:
After driving in the overheated engine protection
operating mode, to avoid engine damage, allow
the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair
the cause of coolant loss, change the oil and reset
the oil life system. Repair the cause of coolant
loss and change the oil. See ªEngine Oilº in
the Index.

6-20
How to Reset the CHANGE ENGINE OIL Message
The GM Oil Life System
calculates when to
change your engine oil and filter based on vehicle use.
Anytime your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE ENGINE OIL message being turned on,
reset the system.
To reset the CHANGE ENGINE OIL message do
the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within five seconds.
If the CHANGE ENGINE OIL message flashes for
five seconds, the system is reset.What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Don't let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good hand
cleaner. Wash or properly throw away clothing or rags
containing used engine oil. See the manufacturer's
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
filter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or
into streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of your used oil, ask your
dealer, a service station or a local recycling center
for help.

6-21
Engine Air Cleaner/Filter
The engine air cleaner/filter assembly has an indicator
that lets you know when the air filter is dirty and needs
to be serviced. The indicator is located on the air cleaner
cover. See ªEngine Compartment Overviewº in the
Index for more information on location.
See ªOwner Checks and Servicesº in the Index to
determine when to check the indicator.
The service window A with
the percentage scale shows
the amount of engine air
cleaner/filter life used.
When both service
window A and service
window B turn orange,
replace the engine
air cleaner/filter.
After changing the air filter, press the top button on the
indicator to reset it.
Your engine air cleaner/filter is located in the front
corner of the engine compartment on the passenger's
side of the vehicle. See ªEngine Compartment
Overviewº in the Index for more information
on location.

Scheduled Maintenance
7-6Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and filter as indicated by the
GM Oil Life System (or every 12 months,
whichever occurs first). Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly,
you must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL message will
come on. Change your oil as soon as possible within the
next two times you stop for fuel. It is possible that, if
you are driving under the best conditions, the oil lifesystem may not indicate that an oil change is necessary
for over a year. However, your engine oil and filter must
be changed at least once a year and at this time the
system must be reset. It is also important to check your
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed. See ªOil Life Systemº in the Index
for information on resetting the system.
An Emission Control Service.
Lubricate chassis components with each engine oil and
filter change. Lubricate the front suspension, ball joints,
steering linkage, transmission shift linkage, transfer case
shift linkage, and parking brake cable guides. Ball joints
should not be lubricated unless their temperature is
10
F (
-12
C) or higher, or they could be damaged.