2004 BUICK CENTURY service

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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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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Radio Messages
CAL (CALIBRATE):Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been congured properly for your vehicle and must
be returned to the dealer for service.
Playing a CD
Insert a CD partway into the slot, label side up. The
player will pull it in. The CD should begin playing. If you
want to insert a CD while the ignition or the radio is
off, rst press the eject or DISP button.
If you turn off the ignition or radio with a CD in the
player, it will stay in the player. When you turn on the
ignition or system, the CD will start playing where
it stopped, if it was the last selected audio source.
As each new track starts to play, the track number will
appear on the display.
The CD player can play the smaller 8 cm single CDs
with an adapter ring. Full-size CDs and the smaller CDs
are loaded in the same manner.
If playing a CD-R the sound quality may be reduced
due to CD-R quality, the method of recording, the quality
of the music that has been recorded, and the way the
CD-R has been handled. You may experience an
increase in skipping, difficulty in nding tracks, and/or
difficulty in loading and ejecting. If these problems occur
try a known good CD.Do not add paper labels to CDs, they could get caught
in the CD player.
Do not play 3 inch CDs without a standard adapter CD.
If an error appears on the display, see “CD Messages”
later in this section.
1
s(Reverse):Press and hold this pushbutton to
reverse quickly within a track. You will hear sound at a
reduced level. Release it to play the passage. The
display will show the elapsed time of the track.
2
\(Forward):Press and hold this pushbutton to
advance quickly within a track. You will hear sound at a
reduced level. Release it to play the passage. The
display will show the elapsed time of the track.
4 RDM (Random):Press this pushbutton to hear the
tracks in random, rather than sequential, order.
Press RDM again to turn off random play.
DISP (Display):Press this button to see which track is
playing. Press it again within ve seconds to see
how long it has been playing. To change the default on
the display (track or elapsed time), press this button
until you see the display you want, then hold the button
until the display ashes. The selected display will
now be the default.
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Radio Messages
CAL (CALIBRATE):Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been congured properly for your vehicle and must
be returned to the dealer for service.
Playing a Cassette Tape
You tape player is built to work best with tapes that are
up to 30 to 45 minutes long on each side. Tapes longer
than that are so thin they may not work well in this player.
The longer side with the tape visible should face to the
right. If the ignition and the radio are on, the tape can be
inserted and will begin playing. If you hear nothing or hear
a garbled sound, the tape may not be in squarely. Press
the eject button to remove the tape and start over.
While the tape is playing, use the VOLUME and AUDIO
controls just as you do for the radio. The display will
show an arrow to show which side of the tape is playing.
If you want to insert a tape while the ignition or radio
is off, rst press the eject or DISP button. Cassette tape
adapter kits for portable CD players will work in your
cassette tape player.
Your tape bias is set automatically when a metal or
chrome tape is inserted.
If an error appears on the display, see “Cassette Tape
Messages” later in this section.1
s(Reverse):Press this pushbutton to reverse
quickly within the tape. The radio will play while the tape
reverses. Press it again to return to playing speed.
2
\(Forward):Press this pushbutton to advance
quickly within the tape. The radio will play while the tape
advances. Press this pushbutton again to return to
playing speed.
6 SIDE:Press this pushbutton to play the other side of
the tape.
©SEEK¨:Your tape must have at least three
seconds of silence between each selection for seek to
work. Press the left or the right arrow to go to the
previous or to the next selection on the tape. SEEK and
a negative or positive number will be displayed.
Pressing the left or right arrow multiple times will
increase the number of selections to be searched up
to -5 or +5. If -5 or +5 is shown on the display the
cassette tape player will fast forward or rewind through
the four selections and stop at the fth selection.
To scan cassette tape selections, press and hold either
SEEK arrow for two seconds until SCN appears on
the display. You will hear a beep. The tape will go to the
next selection, play for a few seconds, then go on to
the next selection. The cassette tape will only scan
forward. Press either SEEK arrow again to stop
scanning.
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