2005 BUICK CENTURY engine

Outlet Adjustment
Use the louvers located on the air outlets to change the
direction of the airow.
Operation Tips

Clear away any ice, snow or leaves from the air
inlets at the base of the vehicle that may block
the ow of air into your 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 your vehicle
more effectively.
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. Turn the ignition to 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.
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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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When the ignition is on, the brake system warning light
will also come on when the parking brake is set.
The light will stay on if the parking brake does not
release fully. If it stays on after the parking brake is
fully released, it means there is a brake problem.
If the light comes on while the vehicle is being driven,
pull off the road and stop carefully. The pedal may
be harder to push, or it may go closer to the oor. It may
take longer to stop. If the light is still on, have the
vehicle towed for service. SeeTowing Your Vehicle on
page 4-36.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed
for service.
Anti-Lock Brake System
Warning Light
If 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 5-69. 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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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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