2003 BUICK CENTURY maintenance

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-6
Safety Belts
.............................................. 1-7
Child Restraints
.......................................1-30
Air Bag Systems
......................................1-53
Restraint System Check
............................1-63
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
......................................2-10
Windows
.................................................2-15
Theft-Deterrent Systems
............................2-17
Starting and Operating Your Vehicle
...........2-19
Mirrors
....................................................2-32
OnStar
žSystem
......................................2-34
Storage Areas
.........................................2-35
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-17
Warning Lights, Gages and Indicators
.........3-22
Audio System(s)
.......................................3-39Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-32
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-5
Checking Things Under the Hood
...............5-10
Headlamp Aiming
.....................................5-49
Bulb Replacement
....................................5-51
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-57
Appearance Care
.....................................5-79
Vehicle Identi®cation
.................................5-87
Electrical System
......................................5-88
Capacities and Speci®cations
.....................5-94
Normal Maintenance Replacement Parts
......5-95
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance Information
.................. 7-2
Reporting Safety Defects
...........................7-10
Index................................................................ 1
2003 Buick Century Owner ManualM

Servicing Your Air Bag-Equipped
Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag systems in several places
around your vehicle. Your dealer and the service manual
have information about servicing your vehicle and the air
bag systems. To purchase a service manual, see
Service
Publications Ordering Information on page 7-11.
{CAUTION:
For up to 10 seconds after the ignition key is
turned off and the battery is disconnected, an
air bag can still in¯ate during improper
service. You can be injured if you are close to
an air bag when it in¯ates. Avoid yellow
connectors. They are probably part of the air
bag system. Be sure to follow proper service
procedures, and make sure the person
performing work for you is quali®ed to do so.
The air bag systems do not need regular maintenance.
1-62

Restraint System Check
Checking Your Restraint Systems
Now and then, make sure the safety belt reminder light
and all your belts, buckles, latch plates, retractors
and anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired.
Torn or frayed safety belts may not protect you in a
crash. They can rip apart under impact forces. If a belt
is torn or frayed, get a new one right away.
Also look for any opened or broken air bag covers, and
have them repaired or replaced. (The air bag system
does not need regular maintenance.)
Replacing Restraint System Parts
After a Crash
{CAUTION:
A crash can damage the restraint systems in
your vehicle. A damaged restraint system may
not properly protect the person using it,
resulting in serious injury or even death in a
crash. To help make sure your restraint
systems are working properly after a crash,
have them inspected and any necessary
replacements made as soon as possible.
1-63

Outlet Adjustment
Open and close the air
outlets, or adjust the
direction of the air¯ow by
moving the levers in
the center of each outlet.
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 your vehicle.
·Use of non-GM approved hood de¯ectors 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.
·If the air¯ow seems low when the fan is at the
highest setting, the passenger compartment
air ®lter, if equipped, may need to be replaced. For
more information, see
Passenger Compartment
Air Filter on page 3-20andPart A: Scheduled
Maintenance Services on page 6-4
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 your engine's air
cleaner ®lter, it may need to be changed periodically.
For information on how often to change the passenger
compartment air ®lter, see
Scheduled Maintenance
on page 6-5.
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.
3-20

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 (peel back halfway
to center).
6. Remove the three air inlet grille retainers.
7. Remove the air inlet grille.
8. Replace the old air ®lter by pulling up on its tab. For
the type of ®lter to use, see
Normal Maintenance
Replacement Parts on page 5-95.9. Install a new passenger compartment air ®lter.
Make sure it slides under the compartment
retainers.
10. Reverse steps 1 through 7.
3-21

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.
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:Modi®cations 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.
Modi®cations 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 doesn't come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
3-31

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.
3-33

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
·start your engine,
·shift into a gear, and
·release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transaxle ¯uid (don't over®ll),
engine oil, drive belt, cooling system and brake system.
Each of these is covered in this manual, and the
Index will help you ®nd them quickly. If you're trailering,
it's a good idea to review this information before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating
on page 5-26.
4-41