2004 BUICK CENTURY service

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-5
Safety Belts
.............................................. 1-6
Child Restraints
.......................................1-28
Air Bag Systems
......................................1-49
Restraint System Check
............................1-58
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
...........2-18
Mirrors
....................................................2-31
OnStar
®System
......................................2-33
Storage Areas
.........................................2-34
Sunroof
..................................................2-36
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-18
Warning Lights, Gages and Indicators
.........3-27
Audio System(s)
.......................................3-44Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-31
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
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
.....................................5-88
Vehicle Identication
.................................5-96
Electrical System
......................................5-97
Capacities and Specications
...................5-103
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
2004 Buick Century Owner ManualM

In many crashes severe enough to inate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from the
right front passenger air bag.
Air bags are designed to inate only once. After an
air bag inates, you will need some new parts for
your air bag system. If you do not get them, the air
bag system will not be there to help protect you
in another crash. A new system will include air bag
modules and possibly other parts. The service
manual for your vehicle covers the need to replace
other parts.
Your vehicle is equipped with a crash sensing and
diagnostic module, which records information
about the frontal air bag system. The module
records information about the readiness of the
system, when the system commands air bag
ination and driver’s safety belt usage at
deployment. The module also records speed,
engine rpm, brake and throttle data.
Let only qualied technicians work on your air bag
systems. Improper service can mean that an air
bag system will not work properly. See your dealer
for service.
Notice:If you damage the covering for the driver’s
or the right front passenger’s air bag, or the air
bag covering on the driver’s seatback, the bag may
not work properly. You may have to replace the
air bag module in the steering wheel, both the air
bag module and the instrument panel for the
right front passenger’s air bag, or the air bag
module and seatback for the driver’s side impact air
bag. Do not open or break the air bag coverings.
1-57

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,
seeService 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 inate during improper
service. You can be injured if you are close to
an air bag when it inates. 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 qualied to do so.
The air bag systems do not need regular maintenance.
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.)
1-58

Remote Keyless Entry System
Your keyless entry system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.At times you may notice a decrease in range. This is
normal for any remote keyless entry system. If the
transmitter does not work or if you have to stand closer
to your vehicle for the transmitter to work, try this:
Check the distance. You may be too far from your
vehicle. You may need to stand closer during
rainy or snowy weather.
Check the location. Other vehicles or objects may
be blocking the signal. Take a few steps to the
left or right, hold the transmitter higher, and
try again.
Check to determine if battery replacement is
necessary. See “Battery Replacement” under
Remote Keyless Entry System Operation on
page 2-5.
If you are still having trouble, see your dealer or a
qualied technician for service.
2-4

The ignition key must be clean and dry before it is
inserted in the ignition or the engine may not start. If the
engine does not start and the SECURITY warning
light on the instrument panel is ashing, the key may be
dirty or wet. Turn the ignition off.
Clean and dry the key. Wait about three minutes and try
again. If the vehicle still does not start, the ignition
key may be faulty. Wait about three more minutes and
try a spare ignition key. At this time, you may also
want to check the fuse. SeeFuses and Circuit Breakers
on page 5-97for information on fuse location. If the
starter will not work with the spare key, the vehicle
needs service. See your dealer or a locksmith who can
service the PASS-Key
®II.
If a key is accidentally used that has a damaged or
missing resistor pellet, the starter will not work.
The SECURITY warning light on the instrument panel
will then come on. But you do not have to wait three
minutes before trying another ignition key.
See your dealer or a locksmith who can service the
PASS-Key
®II to have a new key made.
If the SECURITY warning light comes on the instrument
panel while the vehicle is being driven, the engine
will still be able to be started after it is turned off. The
PASS-Key
®II system, however, is not working properly
and must be serviced by your dealer. The vehicle is
not protected by the PASS-Key
®II system when
this happens.If a PASS-Key
®II ignition key is lost or damaged,
see your dealer or a locksmith who can service
PASS-Key
®II to have a new key made. Also, see
Roadside Assistance Program on page 7-5for more
information.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
“break-in.” But it will perform better in the long run
if you follow these guidelines:
Do not drive at any one speed — fast or
slow — for the rst 500 miles (805 km). Do not
make full-throttle starts.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time your new
brake linings are not yet broken in. Hard stops
with new linings can mean premature wear
and earlier replacement. Follow this breaking-in
guideline every time you get new brake
linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-39for more information.
2-18

Ignition Positions
With the ignition key in the ignition, the key can be
turned to ve different positions:
A (ACCESSORY):This position lets the radio and
windshield wipers operate when the engine is off.
To use ACCESSORY, push in the key and turn it
counterclockwise. The steering wheel will stay locked.B (LOCK):This is the only position in which the ignition
key can be inserted or removed. This position locks
the ignition, steering wheel and transaxle. It is a
theft-deterrent feature.
Notice:If your key seems stuck in LOCK and you
can not turn it, be sure you are using the correct
key; if so, is it all the way in? If it is, then turn the
steering wheel left and right while you turn the
key hard. Turn the key only with your hand. Using a
tool to force it could break the key or the ignition
switch. If none of these works, then your vehicle
needs service.
C (OFF):In this position the engine is off but the
steering wheel is not locked and can still be turned.
Use the OFF position if the vehicle must be pushed
or towed.
D (RUN):This position is where the key returns to after
the vehicle is started. This position displays some of
the warning and indicator lights.
E. (START):This position starts the engine.
A warning chime will sound when the driver’s door is
opened if the ignition is in OFF, LOCK or ACCESSORY
and the key is in the ignition.
2-19

Notice:Driving your vehicle if you notice that it
is moving slowly or not shifting gears as you
increase speed may damage the transaxle. Have
your vehicle serviced right away. You can drive in
SECOND (2) when you are driving less than 35 mph
(55 km/h) and AUTOMATIC OVERDRIVE (D) for
higher speeds until then.
AUTOMATIC OVERDRIVE (
X): This position is for
normal driving. If more power is needed for passing,
and the vehicle is:
Going less than 35 mph (55 km/h), push the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator pedal all the way down.
By doing this the vehicle will shift down to the next gear
and have more power.
THIRD (3): This position is also used for normal driving,
but it offers more power and lower fuel economy than
AUTOMATIC OVERDRIVE (
X).
Here are some times you might choose THIRD (3)
instead of AUTOMATIC OVERDRIVE (
X):
When driving on hilly, winding roads.
When towing a trailer, so there is less shifting
between gears.
When going down a steep hill.
When driving in no-highway scenarios such as city
streets.
Notice:Driving in SECOND (2) for more than
25 miles (40 km) or at speeds over 55 mph (90 km/h)
may damage the transaxle. Also, shifting into
SECOND (2) at speeds above 65 mph (105 km/h) can
cause damage. Drive in THIRD (3) or AUTOMATIC
OVERDRIVE (D) instead of SECOND (2).
SECOND (2): This position gives the vehicle more
power than THIRD (3) but lower fuel economy
than THIRD (3). You can use SECOND (2) on hills.
It can help control the speed going down steep mountain
roads, but then you would also want to use your
brakes off and on.
FIRST (1): This position gives the vehicle even more
power but lower fuel economy than SECOND (2). It can
be used on very steep hills, or in deep snow or mud.
If the shift lever is put in FIRST (1), the transaxle will not
shift into rst gear until the vehicle is going slowly
enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transaxle. If you are stuck,
do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
2-24

Mirrors
Manual Rearview Mirror
Adjust all the mirrors so you can see clearly when
sitting in a comfortable driving position.
To reduce glare from other vehicles’ headlamps, pull the
lever at the bottom of the mirror, to the night position.
To return the mirror to the day position, push the lever.
Manual Rearview Mirror with
OnStar
®
The vehicle may have a mirror with Onstar®. It has a
lever located at the bottom between the two lamps.
To reduce glare from other vehicles’ headlamps, pull the
lever to the night position. For the day position, push
the lever to its original position.
There are two lamps located on the bottom of the
mirror. Press the button located next to each lamp
to turn it on or off.There are also three OnStar
®buttons located at the
bottom of the mirror. See your dealer for more
information on the system and how to subscribe to
OnStar
®. SeeOnStar®System on page 2-33for more
information about the services OnStar®provides.
2-31