1999 BUICK CENTURY Owner's Manual

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Brakes
Brake Fluid
Your brake master cylinder reservoir is on the driver's
side of the engine compartment. It is filled with DOT
-3
brake fluid.
There are only two reasons why the brake fluid level in the
reservoir might go down. The first is that the brake fluid
goes down to an acceptable level during normal brake
lining wear. When new linings are put in, the fluid level
goes back up. The other reason is that fluid is leaking outof the brake system. If it is, you should have your brake
system fixed, since a leak means that sooner or later your
brakes won't work well, or won't work at all.
So, it isn't a good idea to ªtop offº your brake fluid.
Adding brake fluid won't correct a leak. If you add fluid
when your linings are worn, then you'll have too much
fluid when you get new brake linings. You should add
(or remove) brake fluid, as necessary, only when work is
done on the brake hydraulic system.
CAUTION:
If you have too much brake fluid, it can spill on
the engine. The fluid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work is done on the brake
hydraulic system.
When your brake fluid falls to a low level, your brake
warning light will come on. See ªBrake System Warning
Lightº in the Index.

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What to Add
When you do need brake fluid, use only DOT
-3 brake
fluid. Use new brake fluid from a sealed container only.
Refer to ªRecommended Fluids and Lubricantsº in the
Maintenance Schedule.
Always clean the brake fluid reservoir cap and the area
around the cap before removing it. This will help keep
dirt from entering the reservoir.
CAUTION:
With the wrong kind of fluid in your brake
system, your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brake fluid.
NOTICE:

Using the wrong fluid can badly damage
brake system parts. For example, just a few
drops of mineral
-based oil, such as engine
oil, in your brake system can damage brake
system parts so badly that they'll have to be
replaced. Don't let someone put in the
wrong kind of fluid.

If you spill brake fluid on your vehicle's
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle. If you do, wash it off
immediately. See ªAppearance Careº in
the Index.

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6-29 Brake Wear
Your vehicle has front disc brakes and rear drum brakes.
Disc brake pads have built
-in wear indicators that make
a high
-pitched warning sound when the brake pads
are worn and new pads are needed. The sound may
come and go or be heard all the time your vehicle is
moving (except when you are pushing on the brake
pedal firmly).
CAUTION:
The brake wear warning sound means that soon
your brakes won't work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts in the
proper sequence to GM specifications.
Brake linings should always be replaced as complete
axle sets.
See ªBrake System Inspectionº in Section 7 of this
manual under Part C ªPeriodic Maintenance
Inspections.º
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you apply the brakes, with or without the
vehicle moving, your brakes adjust for wear.

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6-30 Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top
-quality GM brake
parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and you have to have new ones put in
-- be sure
you get new approved GM replacement parts. If you
don't, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you've come to expect can change in many
other ways if someone puts in the wrong replacement
brake parts.
Battery
Your new vehicle comes with an ACDelco Freedom

battery. When it's time for a new battery, we
recommend an ACDelco Freedom battery. Get one that
has the replacement number shown on the original
battery's label.
Vehicle Storage
If you're not going to drive your vehicle for 25 days
or more, remove the black, negative (
-) cable from the
battery. This will help keep your battery from
running down.
CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren't careful. See ªJump Startingº in the Index
for tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your vehicle
for longer storage periods.
Also, for your audio system, see ªTheft
-Deterrent
Featureº in the Index.

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Bulb Replacement
In this section you'll find directions for changing the
bulbs on your vehicle. See ªReplacement Bulbsº in the
Index to find the type of bulb you should use.
For any bulb changing procedure not listed in this
section, contact your dealer service department.
Halogen Bulbs
CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
1. Open the hood.
2. Pull up on the headlamp retainers to release the
assembly locator tabs.
3. Slide the headlamp assembly out of the slots.
4. Remove the bulb socket from the
headlamp assembly.

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5. Remove the rubber access cover (from behind the
bulb you are replacing).
6. Quarter twist and turn the bulb socket and remove it
from the lamp.
7. Lift the plastic locking tab on the electrical
connector and pull the connector from the headlamp
bulb socket.8. Connect the new headlamp bulb to the wiring harness,
making sure the connector tab snaps into place.
9. Insert the bulb socket into the headlamp assembly.
10. Reverse all steps and reassemble the headlamp
assembly, then check the lamps.
Headlamp Aiming
Your vehicle has a headlamp system equipped with
horizontal and vertical aim indicators. The aim has been
pre
-set at the factory and should need no further
adjustment. This is true even though your vertical and
horizontal aim indicators may not fall exactly on the ª0º
(zero) marks on their scales.
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment may be necessary
if it is difficult to see lane markers (for horizontal aim),
or if oncoming drivers flash their high beams at you (for
vertical aim). If you believe your headlamps need to be
re
-aimed, we recommend that you take it to your dealer
for service; however, it is possible for you to re
-aim
your headlamps as described in the following procedure.

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NOTICE:
To make sure your headlamps are aimed
properly, read all the instructions before
beginning. Failure to follow these instructions
could cause damage to headlamp parts.
The vehicle should be properly prepared as follows:

The vehicle must have all four tires on a perfectly
level surface.

If necessary, pads may be used on an uneven surface.

The vehicle should not have any snow, ice or mud
attached to it.

The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being done.

There should not be any cargo or loading of the
vehicle, except it should have a full tank of fuel and
one person or 160 lbs. (75 kg) on the driver's seat.

Close all doors.

Tires should be properly inflated.

Rock the vehicle to stabilize the suspension.
Driver's Side Headlamp Shown
A. Vertical aim adjustment screw
B. Horizontal aim adjustment screw
Open the hood and locate the vertical and horizontal aim
indicators. The aiming screw for the vertical aim
indicator is at the center of the headlamp cover (A) and
the aiming screw for the horizontal aim indicator is on
the outboard side of the headlamp cover (B).

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Passenger's Side Headlamp Shown
B. Horizontal aim adjustment screw
C. Horizontal block index plate
D. Vertical aiming level
Start with the horizontal aim. The adjustment screws can
be turned with an E8 Torx

socket.Once the horizontal aim is adjusted, then adjust the
vertical aim.
1. Turn the horizontal aiming screw until the indicator
is lined up with zero.
2. Turn the vertical aiming screw until the level bubble
is lined up with zero.
Front Parking and Turn Signal Lamp
1. Remove the headlamp assembly. Refer to the
removal procedure earlier in this section.
2. Remove the rubber bulb access cover.
3. Twist and pull the sidemarker lamp socket
counterclockwise from the headlamp assembly.
4. Holding the base of the bulb, pull the bulb from
the socket.
5. Push the new bulb into the socket.
6. Put the socket back into the headlamp assembly and
turn it clockwise until it is secure.
7. Replace the rubber bulb access cover.
8. Replace the headlamp assembly.