2003 BUICK CENTURY Owner's Manual

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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Security Light
The SECURITY light will
come on when you turn the
key to START and stay on
until the vehicle starts.
It will also ¯ash if your ignition key is too dirty or wet for
the PASS-Key
žII system to read the resistor pellet.
SeePASS-KeyžII on page 2-17.
If the resistor pellet is damaged or missing, the light will
come on.
Cruise Control Light
The CRUISE light comes
on whenever you set the
cruise control, if equipped.
See ªCruise Controlº under
Turn Signal/Multifunction
Lever on page 3-5.
Low Washer Fluid Warning Light
The LOW WASH light will
come on when your
windshield washers are
working and the ¯uid
container is low.
The light will also come on brie¯y when your ignition is
turned on to show that it is working properly.
Door/Trunk Ajar Warning Light
The DOOR/TRUNK light
will come on if your trunk
or any door is not
completely closed.
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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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Here are four things that some owners ask about. All
these things are normal and do not indicate that
anything is wrong with the fuel gage:
·At the gas station, the pump shuts off before the
gage reads full.
·It takes more (or less) fuel to ®ll up than the gage
reads. For example, the gage reads half full, but it
took more (or less) than half of the tank's
capacity to ®ll it.
·The gage pointer may move while cornering,
braking or speeding up.
·The gage may not indicate empty when the ignition
is turned off.
Low Fuel Warning Light
If your fuel is low, a circular light on your instrument
panel cluster will come on and stay on and a chime will
sound periodically until you add fuel.
It will also come on for a few seconds when you ®rst
turn on the ignition as a check to show you it's working.
If it doesn't come on then, have it ®xed.United States
Canada
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