BUICK CENTURY 2003 Owner's Manual

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 modules, the
wiring and the crash sensing and diagnostic module. For
more information on the air bag system, see
Air Bag
Systems on page 1-53.
This light will come on
when you start your
vehicle, and it will ¯ash 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.
{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not in¯ate in a crash, or they
could even in¯ate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should ¯ash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it ®xed so it will
be ready to warn you if there is a problem.
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Charging System Light
The charging system light
will come on brie¯y when
you turn on the ignition,
as a check to show you it's
working. Then it should
go out.If it stays on, or comes on while you are driving, you
may have a problem with the charging system. It could
indicate that you have a loose accessory belt or
another electrical problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the
radio and air conditioner.
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Brake System Warning Light
Your vehicle's hydraulic brake system is divided into two
parts. If one part isn't working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on, there is a brake problem.
Have your brake system inspected right away.
This light should come on brie¯y when you turn the
ignition key to RUN. If it doesn't come on then, have it
®xed so it will be ready to warn you if there's a problem.
When the ignition is on, the brake system warning light
will also come on when you set your parking brake.
The light will stay on if your parking brake doesn't
release fully. If it stays on after your parking brake is
fully released, it means you have a brake problem.If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
¯oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. See
Towing
Your Vehicle on page 4-32.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you've pulled off the road and stopped
carefully, have the vehicle towed for service.
United States
Canada
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Anti-Lock Brake System Warning
Light
If your vehicle has anti-lock brakes, this warning light
will come on for a few seconds when you turn the
ignition key to RUN. If the anti-lock brake system
warning light stays on longer than normal after you've
started your engine, turn the ignition off. Or, if the
light comes on and stays on when you're driving, stop
as soon as possible and turn the ignition off. Then
start the engine again to reset the system. If the light
still stays on, or comes on again while you're driving, the
anti-lock brake system needs service. If the light is on
and the regular brake system warning light isn't on, you
still have brakes, but you don't have anti-lock brakes.
The anti-lock brake system warning light will come
on brie¯y when you turn the ignition key to RUN. This is
normal. If the light doesn't come on then, have it
®xed so it will be ready to warn you if there is a problem.
Enhanced Traction System Warning
Light
If your vehicle has the
Enhanced Traction
System, the warning light
may come on for the
following reasons:
·If you turn the system off by shifting to SECOND (2)
or FIRST (1), the warning light will come on and
stay on. To turn the system back on, shift to
THIRD (3) or AUTOMATIC OVERDRIVE (
X). See
Enhanced Traction System (ETS) on page 4-10.
·If the Enhanced Traction System warning light
comes on and stays on for an extended period
of time when the system is turned on, your vehicle
needs service. Adjust your driving accordingly.
·The warning light will come on when you set your
parking brake with the engine running, and it will
stay on if your parking brake doesn't release fully. United States
Canada
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If the transaxle shift lever is in any position other
than FIRST (1) or SECOND (2) and the warning
light stays on after your parking brake is fully
released, it means there's a problem with the
system.
·If the traction control system is affected by an
engine-related problem, the system will turn off
and the warning light will come on.
When this warning light is on, the system will not limit
wheel spin. Adjust your driving accordingly.
Low Traction Light
If your vehicle has the
Enhanced Traction
System, this light will come
on when the system is
limiting wheel spin.
You may feel or hear the system working, but this is
normal. Slippery road conditions may exist if the low
traction light comes on, so adjust your driving
accordingly. The light will stay on for a few seconds after
the Enhanced Traction System stops limiting wheel spin.
See
Enhanced Traction System (ETS) on page 4-10.The low traction light also comes on brie¯y when you
turn the ignition key to RUN. If the light doesn't come on
then, have it ®xed so it will be there to tell you when
the Enhanced Traction System is active.
Engine Coolant Temperature
Warning Light
This light tells you that
your engine coolant has
overheated or your radiator
cooling fan is not working.
The light will come on brie¯y when your ignition is
turned on to show you that it is working.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
See
Engine Overheating on page 5-26.
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Engine Coolant Temperature Gage
You have a gage that
shows the engine coolant
temperature. If the
gage pointer moves into
the red area, your
engine is too hot!
This reading means the same thing as the warning light.
It means that your engine coolant has overheated. If
you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
See
Engine Overheating on page 5-26.
Tire Pressure Light
Your vehicle may have a
tire pressure monitor that
can alert you to a large
change in the pressure in
one tire.
After the system has ªlearnedº tire pressures with
properly in¯ated tires, the LOW TIRE light will come on
if the pressure in one tire becomes 12 psi (83 kPa)
lower than the other three tires. The tire in¯ation monitor
system won't alert you if the pressure in more than
one tire is low, if the system is not yet calibrated, or if
the vehicle is moving faster than 70 mph (110 km/h).
When the LOW TIRE light comes on, you should stop as
soon as you can and check all your tires for damage.
If a tire is ¯at, see
If a Tire Goes Flat on page 5-66. Also
check the tire pressure in all four tires as soon as you
can. See
In¯ation Ð Tire Pressure on page 5-57.
The light will stay on, while the ignition is on, until you
reset (calibrate) the system. See
Tire Pressure
Monitor System on page 5-58.
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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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