2005 BUICK CENTURY check engine

Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make it
impossible to steal. However, there are ways you
can help.
PASS-Key®II
The vehicle is equipped
with the PASS-Key®II
(Personalized Automotive
Security System)
theft-deterrent system.
PASS-Key
®II is a passive
theft-deterrent system.
It works when the ignition
key is inserted or
removed from the ignition.
PASS-Key
®II uses a resistor pellet in the ignition key
that matches a decoder in the vehicle.When the PASS-Key
®II system senses that the wrong
key has been inserted into the ignition, it shuts down
the vehicle’s starter and fuel systems. The starter will not
work and fuel will not go to the engine for about
three minutes. If someone tries to start the vehicle again
with the wrong key, or uses another incorrect key
during this time, the vehicle will not start. This
discourages someone from randomly trying keys with
different resistor pellets in an attempt to make a match.
The ignition key must be clean and dry before it is
inserted in the ignition or the engine may not start. If the
engine does not start and the SECURITY warning
light on the instrument panel is ashing, the key may be
dirty or wet. Turn the ignition off.
Clean and dry the key. Wait about three minutes and try
again. If the vehicle still does not start, the ignition
key may be faulty. Wait about three more minutes and
try a spare ignition key. At this time, you may also
want to check the fuse. SeeFuses and Circuit Breakers
on page 5-91for information on fuse location. If the
starter will not work with the spare key, the vehicle
needs service. See your dealer or a locksmith who can
service the PASS-Key
®II.
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Retained Accessory Power (RAP)
If the vehicle has Retained Accessory Power (RAP),
certain features will continue to operate for up to
10 minutes after the ignition key is turned to OFF unless
a door is opened.
Starting Your Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position — that is
a safety feature. To restart when you are already
moving, use NEUTRAL (N) only.
Notice:Shifting into PARK (P) with the vehicle
moving could damage the transaxle. Shift into
PARK (P) only when your vehicle is stopped.
1. With your foot off the accelerator pedal, turn your
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm.Notice:Holding your key in START for longer than
15 seconds at a time will cause your battery to
be drained much sooner. And the excessive heat
can damage your starter motor. Wait about
15 seconds between each try to help avoid draining
your battery or damaging your starter.
2. If your engine will not start, or starts but then stops,
it could be ooded with too much gasoline. Try
pushing your accelerator pedal all the way to the
oor and holding it there as you hold the key
in START for not more than 15 seconds at a time.
This clears the extra gasoline from the engine.
Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly.
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Warning Lights, Gages,
and Indicators
This part describes the warning lights and gages that
may be on the vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
the warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briey when you start the
engine just to let you know they are working. If you are
familiar with this section, you should not be alarmed
when this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there is a problem with your vehicle.
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
the warning lights and gages. They are a big help.
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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 5-69. Also check
the tire pressure in all four tires as soon as possible.
SeeInation - Tire Pressure on page 5-60.
The light will stay on, while the ignition is on, until the
system is reset. SeeTire Pressure Monitor System
on page 5-61.
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.
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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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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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