2004 BUICK CENTURY Owner's Manual

Engine Coolant Temperature
Warning Light
This light indicates that the
engine coolant has
overheated or the radiator
cooling fan is not
working.
The light will come on briey when the ignition is turned
on to show that it is working.
If the vehicle has been operating under normal driving
conditions, pull off the road, stop the vehicle and turn off
the engine as soon as possible. SeeEngine
Overheating on page 5-25.
Engine Coolant Temperature Gage
The vehicle has a gage
that shows the engine
coolant temperature. If the
gage pointer moves into
the red area, the engine is
too hot.
This reading indicates the same thing as the warning
light. It means that the engine coolant has overheated. If
the vehicle has been operating under normal driving
conditions, pull off the road, stop the vehicle and turn off
the engine as soon as possible. SeeEngine
Overheating on page 5-25.
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Tire Pressure Light
The vehicle may have a
tire pressure monitor that
indicates a large change
in the pressure in one tire.
The system stores the tire pressures of the vehicle’s
properly inated 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 LOW TIRE light will
not come on 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, stop as soon as
possible and check all the tires for damage. If a tire
is at, seeIf a Tire Goes Flat on page 5-74. Also check
the tire pressure in all four tires as soon as possible.
SeeInation - Tire Pressure on page 5-64.
The light will stay on, while the ignition is on, until the
system is reset. SeeTire Pressure Monitor System
on page 5-65.
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.
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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,
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.
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 does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre 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.
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 “If
the Light Is On Steady” 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 “If
the Light Is On Steady” following. If the light is still
ashing, follow the previous steps, and see your dealer
for service as soon as possible.
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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. SeeFilling 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 5-4. 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, misring, 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,
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.
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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 the vehicle has a an oil
problem, this light may
stay on after the engine is
started, or come on
while you are driving.
This light indicates that oil is not going through the
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 briey when the ignition is
turned on to show that it is working properly. If it
does not come on with the ignition on, there may be
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:
Do not 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:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
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Change Engine Oil Light
The CHANGE OIL SOON
light should come on
briey as a bulb check
when the engine is started.
If the light does not
come on, have it serviced.
If the CHANGE OIL SOON light comes on and stays on
after the engine is started, have the oil changed.
For additional information, see “When to Change Engine
Oil (GM Oil Life System)” underEngine Oil on
page 5-13. To reset the CHANGE OIL SOON light, see
“How to Reset the System” underEngine Oil on
page 5-13.
Security Light
The SECURITY light will
come on when the key is
turned to START, and
will stay on until the
vehicle starts.
It will also ash if the ignition key is too dirty or wet for
the PASS-Key
®II system to read the resistor pellet.
SeePASS-Key®II on page 2-17.
If the resistor pellet is damaged or missing, the light will
come on.
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Cruise Control Light
The CRUISE light comes
on whenever the cruise
control is set. See “Cruise
Control” underTurn
Signal/Multifunction Lever
on page 3-5.
Low Washer Fluid Warning Light
If the LOW WASH light
comes on when the
windshield washer paddle
is used, this indicates
that the uid is low in the
windshield washer
reservoir.
The light will also come on briey when the ignition is
turned on to show that it is working properly.
Door/Trunk Ajar Warning Light
The DOOR/TRUNK light
will come on if the trunk or
any door is not completely
closed.
Service Vehicle Soon Light
The SERVICE VEHICLE
SOON light will come on if
there are certain
non-emission related
vehicle problems.
These problems may not be obvious and may affect
vehicle performance or durability. Consult your
dealership for necessary repairs to maintain top vehicle
performance. The light will come on briey when
ignition is turned on to show that it is working properly.
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