BUICK CENTURY 1999 Owner's Manual

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When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for about eight seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 20 seconds, then it
will flash for about
55 seconds. If the driver's
belt is already buckled,
neither the chime nor the
light will come on.
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 ªAir Bagº in
the Index.
This light will come on
when you start your engine,
and it will flash 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
engine or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

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2-52 Charging System Light
The charging system light
will come on briefly 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.
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
briefly when you turn the
ignition key to RUN. If it
doesn't come on then, have
it fixed so it will be ready
to warn you if there's
a 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 floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. (See ªAnti
-Lock Brake
System Warning Lightº and ªTowing Your Vehicleº in
the Index.)
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.

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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.
Anti-Lock Brake System Warning Light
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 and you don't have
anti
-lock brakes. The brake pedal may be harder to push,
or it may go to the floor. It may take longer to stop. Adjust
your driving accordingly.The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.
Enhanced Traction System Warning Light
(3100 V6 Engine)
The Enhanced Traction System 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 (
). See ªEnhanced Traction Systemº
in the Index.

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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.
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.
Enhanced Traction System Active Light
The light will come on
when your Enhanced
Traction System is limiting
wheel spin.
You may feel or hear the system working, but this is
normal. Slippery road conditions may exist if this light
comes on, so adjust your driving accordingly.

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2-55 Low Traction Light
If you have the Enhanced
Traction System, this light
will also 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 ªEnhanced Traction Systemº in the Index.
The low traction light also comes on briefly when you
turn the ignition key to RUN. If the light doesn't come
on then, have it fixed so it will be there to tell you when
the Enhanced Traction System is active.
Engine Coolant Temperature Light
This light tells you that your
engine coolant has
overheated or your radiator
cooling fan is not working.
The light should come on briefly 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.
The ªProblems on the Roadº section of this
manual shows what to do. See ªEngine Overheatingº
in the Index.

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2-56 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!
That 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.
The ªProblems on the Roadº section of this
manual shows what to do. See ªEngine Overheatingº
in the Index.
Low Coolant Warning Light
If the LOW COOLANT
light comes on, your system
is low on coolant and the
engine may overheat. See
ªEngine Coolantº in the
Index and have your vehicle
serviced as soon as you can.
The light will come on briefly when your ignition is
turned on to show you that it is working properly.

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2-57 Low Tire Light
The low tire inflation
monitor system can alert
you to a large change in
the pressure in one tire.
After the system has ªlearnedº tire pressures with
properly inflated tires, the LOW TIRE light will come
on if low tire inflation in one tire becomes 12 psi (83
kPa) lower than the other three tires. The tire pressure
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 60 mph (95 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 flat, see ªIf a Tire Goes Flatº in the Index.)
Also check the tire pressure in all four tires as soon as
you can. See ªInflation
- Tire Pressureº in the Index.
The light will stay on until you turn off the ignition or
reset the system. See ªLow Tire Inflation Monitor
Systemº in the Index.
The LOW TIRE light also comes on briefly when you
turn the ignition key to RUN. If the light doesn't come
on then, have it fixed so it will be there to tell you if the
pressure in a tire is low or high.

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2-58 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:
Modifications made to the engine, transaxle,
exhaust 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 the SERVICE ENGINE SOON
light to come on. Modifications 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.

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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
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
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 flashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to flash, 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 flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
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 ªFilling Your Tankº in the Index. 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.

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Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make sure to install the fuel cap properly. See
ªFilling Your Tankº in the Index. It will take a few
driving trips to turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel (see
ªFuelº in the Index). 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, misfiring, 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.
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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix any mechanical or electrical
problems that may have developed.
Oil Warning 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 fixed right away.
The oil light could also come on in the
following situations:

The light will come on briefly 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 fixed
right away.)

Sometimes when the engine is idling at a stop, the
light may blink on and off. This is normal.