2003 BUICK CENTURY service

Malfunction Indicator Lamp
Service Engine Soon 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 SERVICE ENGINE SOON light
comes on and a chime will sound 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:Modi®cations made to the engine,
transaxle, 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.
Modi®cations 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 FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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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 ¯ashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to ¯ash, 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
¯ashing, follow the previous steps, and see your dealer
for service as soon as possible.
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
Filling Your Tank on page 5-7. 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.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, mis®ring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
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If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to ®x any
mechanical or electrical problems that may have
developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
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Oil Pressure Light
If you have a problem with
your oil, this light may stay
on after you start your
engine, or come on when
you are driving.
This indicates that oil is not going through your engine
quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil
problem. Have it ®xed right away.
The oil light could also come on in the following
situations:
·The light will come on brie¯y when you turn on the
ignition to show you that it is working properly. If it
doesn't come on with the ignition on, you may
have a problem with the fuse or bulb. Have it ®xed
right away.
·Sometimes when the engine is idling at a stop, the
light may blink on and off. This is normal.
{CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches ®re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
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Low Oil Level Light
If your vehicle is equipped
with an oil level monitoring
system, the LOW OIL
light will come on brie¯y
when the ignition key
is turned on.
If the light does not come on brie¯y, have it ®xed so it
will be ready to warn you if there's a problem.
If the light stays on, stop the vehicle on a level surface
and turn the engine off. Check the oil level using the
engine oil dipstick. See
Engine Oil on page 5-13.Ifthe
light does not come on brie¯y, have the low oil level
sensor system repaired so it will be ready to warn you if
there's a problem.
The oil level monitoring system only checks oil level
during the brief period between key on and engine
crank. It does not monitor engine oil level when
the engine is running. Additionally, an oil level check is
only performed if the engine has been turned off for
a considerable period of time, allowing the oil normally
in circulation to drain back into the oil pan.
Change Engine Oil Light
The CHANGE OIL SOON
light should come on
brie¯y as a bulb check
when you start the engine.
If the light doesn't come
on, have it serviced.
If the CHANGE OIL SOON light comes on and stays on
after you start the engine, have the oil changed.
For additional information, see ªWhen to Change Engine
Oil (GM Oil Life System)º under
Engine Oil on page 5-13.
To reset the CHANGE OIL SOON light, see ªHow to
Reset the Systemº under
Engine Oil on page 5-13.
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Service Vehicle Soon Light
The SERVICE VEHICLE
SOON light will come on if
you have certain
non-emission related
vehicle problems.
These problems may not be obvious and may affect
vehicle performance or durability. Consult a quali®ed
dealership for necessary repairs to maintain top vehicle
performance. The light will come on brie¯y when your
ignition is turned on to show that it is working properly.
Fuel Gage
Your fuel gage tells you about how much fuel you have
left when the ignition is on. When the indicator nears
empty, you still have a little fuel left, but you should get
more soon.
United StatesCanada
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Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren't, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLEAN
PLAYR to indicate that you have used your tape player
for 50 hours without resetting the tape clean timer. If
this message appears on the display, your cassette tape
player needs to be cleaned. It will still play tapes, but
you should clean it as soon as possible to prevent
damage to your tapes and player. If you notice a
reduction in sound quality, try a known good cassette to
see if the tape or the tape player is at fault. If this
other cassette has no improvement in sound quality,
clean the tape player.
For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealership.The cut tape detection feature of your cassette tape
player may identify the cleaning cassette as a damaged
tape, in error. If the cleaning cassette ejects, insert
the cassette at least three times to ensure thorough
cleaning.
You may also choose a non-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to
clean the tape head. This type of cleaning cassette will
not eject on its own. A non-scrubbing action cleaner
may not clean as thoroughly as the scrubbing type
cleaner. The use of a non-scrubbing action, dry-type
cleaning cassette is not recommended.
After you clean the player, press and hold the EJECT
button for ®ve seconds with the ignition on and the radio
power off to reset the CLEAN PLAYR indicator. The
radio will display Ð 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.
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Once you are moving on the freeway, make certain you
allow a reasonable following distance.
Expect to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit, do
not, under any circumstances, stop and back up. Drive
on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted. Reduce your speed
according to your speedometer, not to your sense
of motion. After driving for any distance at higher
speeds, you may tend to think you are going slower
than you actually are.
Before Leaving on a Long Trip
Make sure you're ready. Try to be well rested. If you
must start when you're not fresh Ð such as after a day's
work Ð don't plan to make too many miles that ®rst
part of the journey. Wear comfortable clothing and shoes
you can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it's ready to go. If it needs
service, have it done before starting out. Of course,
you'll ®nd experienced and able service experts in GM
dealerships all across North America. They'll be
ready and willing to help if you need it.Here are some things you can check before a trip:
·Windshield Washer Fluid:Is the reservoir full? Are
all windows clean inside and outside?
·Wiper Blades:Are they in good shape?
·Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
·Lamps:Are they all working? Are the lenses clean?
·Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all in¯ated to the
recommended pressure?
·Weather Forecasts:What's the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
·Maps:Do you have up-to-date maps?
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