2005 BUICK CENTURY service schedule

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-6
Safety Belts
.............................................. 1-6
Child Restraints
.......................................1-27
Airbag System
.........................................1-49
Restraint System Check
............................1-58
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
......................................2-10
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-16
Starting and Operating Your Vehicle
...........2-17
Mirrors
....................................................2-29
OnStar
®System
......................................2-31
Storage Areas
.........................................2-33
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-18
Warning Lights, Gages, and Indicators
........3-28
Audio System(s)
.......................................3-44Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
........ 4-2
Towing
...................................................4-36
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-5
Checking Things Under the Hood
...............5-10
Headlamp Aiming
.....................................5-45
Bulb Replacement
....................................5-47
Windshield Wiper Blade Replacement
.........5-52
Tires
......................................................5-53
Appearance Care
.....................................5-82
Vehicle Identication
.................................5-90
Electrical System
......................................5-90
Capacities and Specications
.....................5-96
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-10
Index.................................................................1
2005 Buick Century Owner ManualM

Oil Pressure Light
If the vehicle has 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.
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.
3-40

When You Are Ready to Leave After
Parking on a Hill
1. Apply the regular brakes and hold the pedal down
while you:
Start the engine.
Shift into a gear.
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
The vehicle will need service more often when it pulls a
trailer. SeeScheduled Maintenance on page 6-4for
more information. Things that are especially important in
trailer operation are automatic transaxle uid; which
should not be overlled; 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 trailering, it is a good idea to review this
information before starting on a trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating
on page 5-25.
4-44

{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 backres.
If it is not there and the engine backres,
you could be burned. Do not 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 backre
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 are driving.
Automatic Transaxle Fluid
When to Check and Change
A good time to check the 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 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
If the vehicle is not used under any of these conditions,
change the uid and lter at 100,000 miles (166 000 km).
SeeScheduled Maintenance on page 6-4.
5-19

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
Using Your Maintenance Schedule....................6-2
Scheduled Maintenance...................................6-4
Additional Required Services............................6-6
Maintenance Footnotes...................................6-8Owner Checks and Services............................6-9
At Each Fuel Fill............................................6-9
At Least Once a Month.................................6-10
At Least Once a Year...................................6-10
Recommended Fluids and Lubricants...............6-13
Normal Maintenance Replacement Parts..........6-14
Engine Drive Belt Routing..............................6-15
Maintenance Record.....................................6-16
Section 6 Maintenance Schedule
6-1

This schedule is for vehicles that:
carry passengers and cargo within recommended
limits. You will nd these limits on the tire and
loading information label. SeeLoading Your Vehicle
on page 4-31.
are driven on reasonable road surfaces within legal
driving limits.
use the recommended fuel. SeeGasoline Octane
on page 5-5.
The services inScheduled Maintenance on page 6-4
should be performed when indicated. SeeAdditional
Required Services on page 6-6andMaintenance
Footnotes on page 6-8for further information.
{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,
see your GM Goodwrench dealer to have a
qualied technician do the work.Some maintenance services can be complex. So,
unless you are technically qualied and have the
necessary equipment, you should have your GM
Goodwrench dealer do these jobs.
When you go to your GM Goodwrench dealer for your
service needs, you will know that GM-trained and
supported service technicians will perform the work
using genuine GM parts.
If you want to get service information, seeService
Publications Ordering Information on page 7-11.
Owner Checks and Services on page 6-9tells you what
should be checked, when to check it and what you can
easily do to help keep your vehicle in good condition.
The proper replacement parts, uids and lubricants to
use are listed inRecommended Fluids and Lubricants
on page 6-13andNormal Maintenance Replacement
Parts on page 6-14. When your vehicle is serviced,
make sure these are used. All parts should be replaced
and all necessary repairs done before you or anyone
else drives the vehicle. We recommend the use of
genuine GM parts.
6-3

Scheduled Maintenance
When the CHANGE OIL SOON light comes on, it means
that service is required for your vehicle. Have your
vehicle serviced as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the engine oil life
system may not indicate that vehicle service 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 GM
Goodwrench dealer has GM-trained service technicians
who will perform this work using genuine GM parts
and reset the system.
If the engine oil life system is ever reset accidentally,
you must service your vehicle within 3,000 miles
(5 000 km) since your last service. Remember to reset
the oil life system whenever the oil is changed. See
Engine Oil Life System on page 5-16for information on
the Engine Oil Life System and resetting the system.When the CHANGE OIL SOON light appears, certain
services, checks and inspections are required.
Required services are described in the following for
“MaintenanceI” and “MaintenanceII.” Generally, it is
recommended that your rst service be MaintenanceI,
your second service be MaintenanceIIand that you
alternate MaintenanceIand MaintenanceIIthereafter.
However, in some cases, MaintenanceIImay be
required more often.
MaintenanceI— Use MaintenanceIif the light comes
on within ten months since vehicle was purchased or
MaintenanceIIwas performed.
MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the light comes on ten months
or more since the last service or if the light has not
come on at all for one year.
6-4

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-13. Reset oil life system.
SeeEngine Oil Life System on page 5-16.An Emission Control Service.••
Visually check for any leaks or damage.See footnote (k).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-18.An Emission Control Service. See footnote †.••
Rotate tires and check ination pressures and wear. SeeTires on page 5-53.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid
as needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transaxle uid level and add uid as needed.•
Replace passenger compartment air lter.See footnote (g).•
Inspect throttle system.See footnote (j).•
6-5