BUICK CENTURY 2004 Owner's Manual

Headlamp Aiming
The 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 the vertical and
horizontal aim indicators may not fall exactly on
the “0” (zero) marks on their scales.
If the 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 ash their high
beams at you, for vertical aim. If you believe the
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 the headlamps as described
in the following procedure.
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.To check the aim, the vehicle should be properly
prepared as follows:The headlamps must be off for one hour prior to
aiming and must remain off during this procedure.
The vehicle must have all four tires on a perfectly
level surface.
If necessary, pads may be used on an uneven
surface to help level the vehicle.
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. It should however, have a full fuel
tank and one person or 160 lbs (75 kg) on
the driver’s seat.
Close all doors.
Tires should be properly inated.
Rock the vehicle to stabilize the suspension.
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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 (A) is at the center of the headlamp cover
and the aiming screw for the horizontal aim indicator (B)
is on the outboard side of the headlamp cover.A. Horizontal Aim Adjustment Screw
B. Horizontal Block Index Plate
C. 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. Driver’s Side Headlamp Shown
Passenger’s Side Headlamp Shown
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Bulb Replacement
For any bulb changing procedure not listed in this
section, contact your dealer. For the type of bulb, see
Replacement Bulbs on page 5-55.
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 (A) to release the
assembly locator tabs.
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3. Disconnect the electrical connector (B) from the
headlamp assembly.
4. Slide the headlamp assembly out of the slots.
5. Remove the rubber access cover from behind the
bulb being replaced.
6. Turn the bulb socket one-quarter turn and remove it
from the headlamp assembly.
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 electrical
connector, making sure the connector tab snaps
into place.
9. Insert the bulb socket into the headlamp assembly.
10. Reverse all steps to reassemble the headlamp
assembly, then check the lamps.
Front Turn Signal and Parking
Lamps
1. Remove the headlamp assembly. Refer to the
removal procedure earlier in this section.
2. Remove the rubber bulb access cover.
3. Twist the sidemarker lamp socket, located on the
outboard side of the headlamp assembly,
counterclockwise and pull it from the headlamp
assembly.
4. Holding the base of the socket, pull the old bulb
from the socket.
5. Push the new bulb into the socket.
6. Reverse Steps 1 through 3 to reinstall the lamp
assembly.
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Center High-Mounted
Stoplamp (CHMSL)
1. Open the trunk.
2. Reach through the access opening in the trunk lid.3. Remove the old bulb by turning it counterclockwise
one-quarter turn.
4. Push the new bulb into the bulb socket.
5. Turn the socket clockwise one-quarter turn to
reinstall.
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Taillamps, Turn Signal, and
Stoplamps1. Open the trunk.
2. Remove the convenience net If the vehicle
has one.
3. Remove the three plastic wing nuts (A).
One wing nut is located on top of the carpet. The
other two are located underneath the carpet.
4. Pull the taillamp housing (B) away from the body of
the vehicle.
5. Squeeze the tab on the socket and turn the socket
counterclockwise.
6. Pull out the socket.
7. Pull the old bulb out of the socket. There are two
bulbs on each taillamp.
8. Push in a new bulb.
9. Reverse these steps to reinstall the lamp assembly.
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Back-Up Lamps
1. Open the trunk.
2. Remove the seven hex nuts (A) from the lamp
covering.
3. Remove the lamp covering.4. Twist and pull the bulb socket (B) from the trunk lid.
5. Twist and pull the old bulb from the bulb socket.
6. Twist and push the new bulb into the lamp socket.
7. Twist and push the lamp socket into the trunk
lid covering.
8. Reverse Steps 2 and 3 to reinstall the lamp
covering.
Replacement Bulbs
Exterior Lamps Bulb Number
Back-Up Lamps 1156
Center High-Mounted
Stoplamp (CHMSL)3155
Front Turn Signal and Parking
Lamps4157NAK
High-Beam Headlamps 9005
Low-Beam Headlamps 9006
Taillamps and Stoplamps/Turn
Signal3057
Taillamp 194
For any bulb not listed here contact your dealer.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking each time maintenance is performed.
SeeScheduled Maintenance on page 6-4.
1. Turn on the wipers to LO.
2. Turn off the ignition while the wipers are at the
outer positions of the wiper pattern. The blades
are more accessible for removal or replacement
while in this position.
3. Pull the windshield wiper arm 3 to 4 inches
(7.5 to 10 cm) away from the windshield.
4. While holding the wiper arm away from the glass,
push the release clip from under the windshield
wiper arm connecting point and slide the blade
assembly down toward the glass to remove it from
the wiper arm.
5. Slide the new wiper blade securely on the wiper
arm until you hear the release clip click into
place. SeeNormal Maintenance Replacement Parts
on page 6-13for the type of windshield wiper
blades to use.
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GM Warranty booklet for details. For additional
information refer to the tire manufacturer’s booklet
included with your vehicle’s Owner’s Manual.{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See “Loading Your
Vehicle” in the Index.
Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinated tires are more likely to be
cut, punctured or broken by a sudden
impact — such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If
your tread is badly worn, or if your tires
have been damaged, replace them.
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Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical passenger
car tire and a compact spare tire sidewall.
Passenger Car Tire Example
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