service schedule BUICK CENTURY 2003 Owner's Manual

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

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

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

{CAUTION:
Operating the engine with the air cleaner/®lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stop ¯ame if the engine back®res. If it isn't there
and the engine back®res, you could be burned.
Don't drive with it off, and be careful working on
the engine with the air cleaner/®lter off.
Notice:If the air cleaner/®lter is off, a back®re can
cause a damaging engine ®re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/®lter in place when
you're driving.
Automatic Transaxle Fluid
When to Check and Change
A good time to check your automatic transaxle ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
·In heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter at 100,000 miles
(166 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
5-19

Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment. Also
check for damaged tires or wheels. See
When It Is Time
for New Tires on page 5-61andWheel Replacement
on page 5-64for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The ®rst rotation
is the most important. See ªPart A: Scheduled
Maintenance Services,º in Section 6, for scheduled
rotation intervals.When rotating your tires, always use the correct rotation
pattern shown here.
Don't include the compact spare tire in your tire rotation.
After the tires have been rotated, adjust the front and
rear in¯ation pressures as shown on the Tire-Loading
Information label.
Reset the Tire In¯ation Monitor System. See
Tire
Pressure Monitor System on page 5-58.
Make certain that all wheel nuts are properly tightened.
See ªWheel Nut Torqueº under
Capacities and
Speci®cations on page 5-94.
5-60

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-10
At Each Fuel Fill..........................................6-10
At Least Once a Month.................................6-10
At Least Twice a Year...................................6-11At Least Once a Year...................................6-11
Part C: Periodic MaintenanceInspections.........6-14
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-14
Exhaust System Inspection............................6-14
Fuel System Inspection..................................6-14
Engine Cooling System Inspection...................6-14
Throttle System Inspection.............................6-15
Brake System Inspection................................6-15
Part D: Recommended Fluids and Lubricants. . . .6-16
Part E: Maintenance Record...........................6-17
Section 6 Maintenance Schedule
6-1

How This Section is Organized
This maintenance schedule is divided into ®ve parts:
ªPart A: Scheduled Maintenance Servicesºexplains
what to have done and how often. Some of these
services can be complex, so unless you are technically
quali®ed and have the necessary equipment, you should
let your GM dealer's service department do these jobs.
Your GM dealer has GM-trained and supported service
people that will perform the work using genuine GM parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
have a quali®ed technician do the work.
If you want to get the service information, see
Service
Publications Ordering Information on page 7-11.ªPart B: Owner Checks and Servicesºtells you what
should be checked and when. It also explains what
you can easily do to help keep your vehicle in good
condition.
ªPart C: Periodic MaintenanceInspectionsºexplains
important inspections that your dealer's service
department can perform for you.
ªPart D: Recommended Fluids and Lubricantsºlists
some recommended products necessary to help
keep your vehicle properly maintained. These products,
or their equivalents, should be used whether you do
the work yourself or have it done.
ªPart E: Maintenance Recordºis a place for you to
record and keep track of the maintenance performed on
your vehicle. Keep your maintenance receipts. They may
be needed to qualify your vehicle for warranty repairs.
6-3

Part A: Scheduled Maintenance
Services
This part contains engine oil scheduled maintenance
which explains the engine oil life system and how
it indicates when to change the engine oil and ®lter.
Also, listed are scheduled maintenance services which
are to be performed at the mileage intervals speci®ed.
Using Your Maintenance Schedule
We at General Motors want to keep your vehicle in good
working condition. But we don't know exactly how
you'll drive it. You may drive short distances only a few
times a week. Or you may drive long distances all
the time in very hot, dusty weather. You may use your
vehicle in making deliveries. Or you may drive it to
work, to do errands or in many other ways.
Because of the different ways people use their vehicles,
maintenance needs may vary. You may need more
frequent checks and replacements. So please read the
following and note how you drive. If you have
questions on how to keep your vehicle in good condition,
see your dealer.This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer for your service needs,
you'll know that GM-trained and supported service
people will perform the work using genuine GM parts.
The proper ¯uids and lubricants to use are listed in Part
D. Make sure whoever services your vehicle uses these.
All parts should be replaced and all necessary repairs
done before you or anyone else drives the vehicle.
This schedule is for vehicles that:·carry passengers and cargo within recommended
limits. You will ®nd these on your vehicle's
Tire-Loading Information label. See
Loading Your
Vehicle on page 4-33.
·are driven on reasonable road surfaces within legal
driving limits.
·use the recommended fuel. SeeGasoline Octane
on page 5-5
.
6-4

Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
See
Part B: Owner Checks and Services on page 6-10andPart C: Periodic MaintenanceInspections on
page 6-14.
Footnotes
²The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.Whenever the tires are rotated, the Tire In¯ation Monitor
System must be reset.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-15.
Engine Oil Scheduled Maintenance
Change engine oil and ®lter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs ®rst). Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
6-5

When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL SOON light will
come on. Change your oil as soon as possible within the
next two times you stop for fuel. It is possible that, if
you are driving under the best conditions, the oil
life system may not indicate that an oil change is
necessary for over a year. However, your engine oil and
®lter must be changed at least once a year and at
this time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system.
It is also important to check your oil regularly and keep
it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed. See
Engine Oil on
page 5-13for information on resetting the system.
An Emission Control Service.
See the mileage intervals following for additional
services that may be performed with an engine oil
change. After the services are performed, record the
date, odometer reading and who performed the service
on the maintenance record pages in Part E of this
schedule.
7,500 Miles (12 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote .) (See footnote +.)
15,000 Miles (25 000 km)
qInspect engine air cleaner ®lter. If necessary, replace
the ®lter. If vehicle is driven in dusty/dirty conditions,
inspect ®lter at every engine oil change. See
Engine Air Cleaner/Filter on page 5-18for more
information.An Emission Control Service. (See
footnote ².)
qReplace passenger compartment air ®lter. If you
drive regularly under dusty conditions, the ®lter
may require replacement more often.
qRotate tires. See
Tire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote .) (See footnote +.)
22,500 Miles (37 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote .) (See footnote +.)
6-6