2005 BUICK CENTURY Owner's Manual

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.
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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 “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.
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 5-8.
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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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline 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, 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.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 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.
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.
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For additional information, see “When to Change
Engine Oil (GM Oil Life System)” and “How to Reset
the CHANGE OIL SOON Light ” 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 2-16.
If the resistor pellet is damaged or missing, the light
will come on.
Cruise Control Light
The CRUISE light comes
on whenever the cruise
control is set. See “Cruise
Control” underTurn
Signal/Multifunction Lever
on page 3-7.
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.
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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 GM
dealership for necessary repairs to maintain top vehicle
performance. The light will come on briey when the
ignition is turned on to show that it is working properly.
Fuel Gage
The fuel gage indicates about how much fuel is left in
the fuel tank when the ignition is on. When the indicator
nears empty, there is still a little fuel left, but you
should get more fuel 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 accelerating.
The gage may not indicate empty when the ignition
is turned off.
Low Fuel Warning Light
If the vehicle’s fuel is low, a light on the instrument
panel cluster will come on and a chime will sound
periodically until fuel is added to the fuel tank.
It will also come on for a few seconds when the ignition
is turned on as a check to indicate it is working. If it
does not come on then, have it xed.United States
Canada
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Audio System(s)
Notice:Before adding any sound equipment to
your vehicle, like a tape player, CB radio, mobile
telephone, or two-way radio, make sure that it can
be added by checking with your dealer. Also,
check federal rules covering mobile radio and
telephone units. If sound equipment can be added,
it is very important to do it properly. Added sound
equipment may interfere with the operation of
your vehicle’s engine, radio, or other systems, and
even damage them. Your vehicle’s systems may
interfere with the operation of sound equipment that
has been added improperly.
Figure out which audio system is in your vehicle, nd
out what your audio system can do, and how to operate
all of its controls.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, the audio system can be
played even after the ignition is turned off.
See “Retained Accessory Power (RAP)” under
Ignition Positions on page 2-18.
Setting the Time
Press and hold H until the correct hour appears on the
display. AM will appear for morning hours. Press and
hold M until the correct minute appears on the display.
The time can be set with the ignition on or off.
To synchronize the time with an FM station broadcasting
Radio Data System (RDS) information, press and
hold H and M at the same time until TIME UPDATED
appears on the display. If the time is not available from
the station, NO UPDATE will appear on the display.
RDS time is broadcast once a minute. After tuning to an
RDS broadcast station, it may take a few minutes for
the time to update.
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