2003 GMC YUKON service indicator

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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•If the Traction Assist System is affected by an
anti-lock brake system, TAS or engine-related
problem, the system will turn off and the light will
come on. Have your vehicle serviced.
•If the vehicle is driven over an extremely rough
road, the system will turn off and the light will come
on. The light will go off a few seconds after the
rough road conditions go away or when the vehicle
comes to a complete stop. This is normal
operation.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
fluctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-29.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage. United StatesCanada
United StatesCanada
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This 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—Amisfire condition has been
detected. A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
•Light On Steady—An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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After you clean the player, press and hold the eject
button forfive seconds to reset the CLEAN indicator.
The radio will display—or CLEANED to show the
indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Care of Your CDs and DVDs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust. If the surface of a disc is soiled, dampen
a clean, soft cloth in a mild, neutral detergent solution
and clean it, wiping from the center to the edge.
Be sure never to touch the side without writing when
handling discs. Pick up discs by grasping the outer
edges or the edge of the hole and the outer edge.
Care of Your CD and DVD Player
The use of CD lens cleaner discs is not advised, due to
the risk of contaminating the lens of the CD optics
with lubricants internal to the CD mechanism.
Cleaning the Video Screen
Pour some isopropyl or rubbing alcohol on a clean cloth
and gently wipe the video screen. Do not spray
directly onto the screen and do not press too hard or
too long on the video screen.
Fixed Mast Antenna
Thefixed mast antenna can withstand most car washes
without being damaged. If the mast should ever
become slightly bent, you can straighten it out by hand.
If the mast is badly bent, as it might be by vandals,
you should replace it.
Check occasionally to be sure the mast is still tightened
to the cowl. If tightening is required, tighten by hand,
then with a wrench one quarter turn.
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Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does not
recommend the use of such gasolines. Fuels containing
MMT can reduce the life of spark plugs and the
performance of the emission control system may be
affected. The malfunction indicator lamp may turn on. If
this occurs, return to your authorized GM dealer for
service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identification number (VIN)
shows the code letter or number that identifies your
engine. You willfind the VIN at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-96.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.Only vehicles that have the 5.3L V8 engine
(VIN Code Z) may use 85% ethanol fuel (E-85).
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help youfind
E-85 fuel. Those stations that do have E-85 should have
a label indicating ethanol content. Do not use the fuel
if the ethanol content isgreaterthan 85%. Your vehicle
may not operate properly if the ethanol content is
greater than 85%.
At a minimum, E-85 should meet ASTM
Specification D 5798.
To insure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E-85, it may be because your E-85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed to
accommodate a mixture of gasoline and E-85 fuel.
For good starting and heater efficiency below 32°F
(0°C), the fuel mix in the fuel tank should contain no
more than 70% ethanol.
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Always clean the brakefluid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind ofuid in your brake
system, your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brakeuid.
Notice:
Using the wronguid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they’ll have to be replaced.
Don’t let someone put in the wrong kind ofuid.
If you spill brakeuid on your vehicle’s painted
surfaces, the paintnish can be damaged. Be
careful not to spill brakeuid on your vehicle. If
you do, wash it off immediately. See
“Appearance Care”in the Index.
Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedalfirmly).
{CAUTION:
The brake wear warning sound means that
soon your brakes won’t work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes arefirst applied or lightly
applied. This does not mean something is wrong with
your brakes.
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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. SeeEngine Oil on
page 5-16for 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.
See the mileage intervals following for additional
services that may be performed with an engine oil
change and chassis lubrication. After the services are
performed, record the date, odometer reading and
who performed the service on the maintenance record
pages in Part E of this schedule.7,500 Miles (12 500 km)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
15,000 Miles (25 000 km)
❑Inspect engine air cleanerfilter or change indicator (if
equipped). If necessary, replace thefilter. If vehicle is
driven in dusty/dirty conditions, inspectfilter or
change indicator (if equipped) at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-21
for more information.An Emission Control Service.
(See footnote†.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
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22,500 Miles (37 500 km)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
30,000 Miles (50 000 km)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
❑Replace fuelfilter.An Emission Control Service. (See
footnote†.)
❑Replace engine air cleanerfilter on vehicles without
a restriction indicator. If equipped with a change
indicator, inspect the indicator. If necessary, replace
thefilter. If vehicle is driven in dusty/dirty conditions,
inspect the change indicator (if equipped) at every
engine oil change. SeeEngine Air Cleaner/Filter on
page 5-21for more information.An Emission
Control Service. (See footnote†.)
37,500 Miles (62 500 km)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
45,000 Miles (75 000 km)
❑Inspect engine air cleanerfilter or change indicator (if
equipped). If necessary, replace thefilter. If vehicle is
driven in dusty/dirty conditions, inspectfilter or
change indicator (if equipped) at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-21
for more information.An Emission Control Service.
(See footnote†.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
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