2004 BUICK CENTURY engine

WINDSHIELD/FLOOR:This setting directs some of the
air to the oor outlets and some to the defroster and
side window outlets. The air-conditioning compressor will
run automatically in this setting unless the outside
temperature is below 40°F (4°C).
MID/FLOOR:This mode directs airow through both
the oor and the instrument panel outlets. A small
amount of air is directed to the windshield and the side
window outlets.
MID (Instrument Panel):This mode directs air through
the instrument panel outlets.
FLOOR:This setting sends most of the air through the
outlets near the oor. The rest comes out of the
defroster and side window outlets.
VENT:Press this button to turn the air-conditioning
compressor on or off. The indicator light on the VENT
mode is lit when the compressor is turned off. The
interior brightness control might have to be adjusted to
the highest setting during the day in order to see
the indicator lamp.
VENT does not operate in the FRONT defrost mode.
RECIRC (Recirculation):Press this button to turn this
mode on or off. RECIRC limits the amount of outside
air coming into the vehicle and recirculates most of the
air inside your vehicle. It can be use to preventoutside air and odors from entering the vehicle or to
quickly heat or cool the air inside the vehicle. When this
button is pressed an indicator light will come on. The
interior brightness control might have to be adjusted to
the highest setting during the day in order to see the
indicator lamp.
This setting is not permitted in FRONT defrost mode
and is only permitted in WINDSHIELD/FLOOR mode if
the compressor is turned on.
On hot days, open the windows to let hot air inside
escape; then close them. This helps to reduce the time
it takes for the vehicle to cool down. It also helps the
system to operate more efficiently.
For quick cool down on hot days, press the AUTO
button. The system will automatically enter the
recirculation mode where the temperature will be at the
full cold position for maximum cooling.
The air-conditioning system removes moisture from the
air, so a small amount of water dripping underneath
the vehicle while it is idling or after the engine is turned
off is normal.
Operating the climate control system in the RECIRC
mode may cause fogging of the vehicle’s windows when
the weather is cold and damp. To clear the fog, select
either WINDSHIELD/FLOOR or defrost mode and
increase the speed.
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Operation Tips
Clear away any ice, snow or leaves from the air
inlets at the base of the windshield that may
block the ow of air into the vehicle.
Use of non-GM approved hood deectors may
adversely affect the performance of the system.
Keep the path under the front seats clear of objects
to help circulate the air inside of the vehicle more
effectively.
If the vehicle has a passenger compartment air lter
and the airow seems low when the fan is at the
highest setting it may need to be replaced. For more
information, seePassenger Compartment Air
Filter on page 3-26.
Passenger Compartment Air Filter
The passenger compartment air lter is located in
the engine compartment below the air inlet grille, near
the passenger’s side windshield wiper arm.
The lter traps most of the pollen from the air entering
the air conditioning module. Like the engine’s air cleaner
lter, it may need to be changed periodically. For
information on how often to change the passenger
compartment air lter, seeScheduled Maintenance on
page 6-4.To change the passenger compartment air lter, use the
following steps:
1. Put the ignition in ACCESSORY and turn the
windshield wipers on.
2. Turn the ignition to OFF when the windshield
wipers are in the upright position.
3. Raise the hood.
4. Disconnect the windshield washer pump hose from
the fender rail and air inlet grille.
5. Remove the hood weather-strip from the
passenger’s side of the vehicle and peel it back
halfway to the center of the hood.
6. Remove the three air inlet grille retainers.
7. Remove the air inlet grille.
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8. Replace the old air
lter by pulling up on
its tab.
9. Install a new passenger compartment air lter. See
Normal Maintenance Replacement Parts on
page 6-13for the type of lter to use. Make sure it
slides under the compartment retainers.
10. Reverse Steps 1 through 6.
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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Anti-Lock Brake System Warning
LightIf the vehicle has anti-lock brakes, this warning light will
come on for a few seconds when the ignition key is
turned to RUN. If the anti-lock brake system warning
light stays on longer than normal after the engine
has been started, turn the ignition off. Or, if the light
comes on and stays on while the vehicle is being driven,
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 driving,
the anti-lock brake system needs service. If the light is
on and the regular brake system warning light is not
on, the vehicle still has brakes, but it does not have
anti-lock brakes.
The anti-lock brake system warning light will come on
briey when the ignition key is turned to RUN. This
is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem. United States
Canada
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Enhanced Traction System Warning
Light
If the vehicle has the
Enhanced Traction
System, (ETS) the warning
light may come on for
the following reasons:
When the vehicle is shifted to SECOND (2) or
FIRST (1). To turn the system back on, shift
to THIRD (3) or AUTOMATIC OVERDRIVE (
X).
SeeEnhanced Traction System (ETS) on page 4-9.
If the vehicle needs service. Adjust your driving
accordingly.
When the parking brake is set with the engine
running, and the parking brake does not
release fully.
After the parking brake is fully released and the
transaxle shift lever is in any position other
than FIRST (1) or SECOND (2). This means there
is a problem with the system.
If an engine-related problem affects the ETS and
turns the system off.
When the ETS warning light is on, the system will not
limit wheel spin. Adjust your driving accordingly.
Low Traction Light
If the vehicle has the
Enhanced Traction System
(ETS), this light will
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 ETS stops limiting wheel spin. SeeEnhanced
Traction System (ETS) on page 4-9.
The low traction light also comes on briey when the
ignition key is turned to RUN. If the light does not come
on then, have it xed so it will function properly to
indicate when the Enhanced Traction System is active.
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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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