2004 BUICK CENTURY Owner's Manual

5. Check that the jumper cables do not have loose or
missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive (+) terminal if
the vehicle has one. Negative (−) will go to a heavy,
unpainted metal engine part or to a remote
negative (−) terminal if the vehicle has one.
Do not connect positive (+) to negative (−)oryou
will get a short that would damage the battery
and maybe other parts too. And do not connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.
6. Connect the red positive (+) cable to the positive (+)
terminal of the dead battery. Use a remote
positive (+) terminal if the vehicle has one.
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7. Do not let the other
end touch metal.
Connect it to the
positive (+) terminal
of the good battery.
Use a remote
positive (+) terminal
if the vehicle has one.8. Now connect the
negative (−) cable to
the negative (−)
terminal of the good
battery. Use a remote
negative (−) terminal
if the vehicle has one.
Do not let the other end touch anything until the
next step. The other end of the negative (−) cable
does notgo to the dead battery. It goes to a
heavy, unpainted metal part, or to the remote
negative (−) terminal on the vehicle with the dead
battery.
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9. Connect the other end of the negative (−) cable at
least 18 inches (45 cm) away from the dead battery,
but not near engine parts that move. The electrical
connection is just as good there, and the chance
of sparks getting back to the battery is much less.10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle that had the dead battery. If
it will not start after a few tries, it probably needs
service.
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Notice:If the jumper cables are removed in the
wrong order, electrical shorting may occur and
damage the vehicle. The repairs would not be
covered by your warranty. Remove the jumper
cables in the correct order, making sure that the
cables do not touch each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo disconnect the jumper cables from both vehicles do
the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the remote positive (+) terminal cover to its
original position.
Jumper Cable Removal
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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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