2004 CADILLAC DEVILLE headlamp

Headlamp Aiming
Your vehicle has a visual optical headlamp aiming system
which may be equipped with horizontal aim indicators.
The aim has been preset at the factory and should need
no further adjustment. This is true even though your
horizontal aim indicators (if equipped) may not fall exactly
on the “0” (zero) marks on their scales.
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment to the low beam
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 your
headlamps need to be re-aimed, we recommend that
you take your vehicle to your dealer for service.
However, it is possible for you to re-aim your 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.
The vehicle should be properly prepared as follows:
The vehicle should be placed so the headlamps are
25 ft. (7.6 m) from a light colored wall or other at
surface.
The vehicle must have all four tires on a perfectly
level surface which is level all the way to the wall
or other at surface.
The vehicle should be placed so it is perpendicular
to the wall or other at 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.
The vehicle should be normally loaded with a
full tank of fuel and one person or 160 lbs. (75 kg)
on the driver’s seat.
Tires should be properly inated.
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Headlamp aiming is done with the vehicle low-beam
lamps. The high-beam lamps will be correctly aimed if
the low-beam lamps are aimed properly.
The headlamp aiming devices are under the hood near
the headlamps.
If you believe your headlamps need horizontal (left/right)
adjustment, follow the horizontal aiming procedure. If you
believe your headlamps need only vertical (up/down)
adjustment, follow only the vertical aiming procedure.
Adjustment screws can be turned with an E8 Torx
®
socket or T15 Torx®screwdriver.
Headlamp Horizontal Aiming
If your vehicle has the horizontal aim indicators, turn the
horizontal aiming screw (A) until the indicator (B) is
lined up with zero.
Once the horizontal aim is adjusted, then adjust the
vertical aim.
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Headlamp Vertical Aiming
Notice:Horizontal aiming must be performed
before making any adjustments to the vertical aim.
Adjusting the vertical aim rst will result in an
incorrect headlamp aim.
1. Find the aim dot on the lens of the low beam lamps.2. Measure the distance from the ground to the aim
dot on each lamp; if left low beam, subtract two
inches. Record this distance.
3. At the wall or other at surface, measure from the
ground upward the recorded distance from Step 2
and draw or tape a horizontal line the width of
the vehicle.
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4. Turn on the low-beam headlamps and place a
piece of cardboard or equivalent in front of the
headlamp not being aimed. This should allow only
the beam of light from the headlamp being
aimed to be seen on the at surface.
Notice:Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.5. Turn the vertical aiming screw (C) until the
headlamp beam is aimed to the horizontal tape line.
The top edge of the cut-off should be positioned
at the bottom edge of the horizontal tape line.
6. Repeat Steps 4 and 5
for the opposite
headlamp.
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Bulb Replacement
For the proper type of replacement bulb, see
Replacement Bulbs on page 5-64.
For any bulb changing procedure not listed in this
section, contact your dealer.
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. Remove all of the
push-pins that hold the
ller panel cover in
place by pressing in the
center of each pin
and then pulling up on
the outer circle.
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2. Remove the two bolts at the top of the headlamp
assembly.
3. Loosen the bolt at the bottom of the headlamp
assembly.4. Use a tool to help pry the headlamp assembly away
from the vehicle.
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5. Firmly grasp the outboard side of the headlamp
assembly with both hands and pull hard enough
so that the whole assembly separates from
the vehicle.6. Remove the bulb
socket dust cover.
7. Turn the headlamp
housing socket
counterclockwise to
unlock the socket from
the lamp housing.
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8. Pull the old bulb out of
the socket.
9. Install the new bulb into the socket. Make sure that
the bulb is locked in rmly.
10. Reinstall the headlamp housing socket into the
headlamp assembly.
11. Reinstall the headlamp assembly by reversing
Steps 2 through 6.To reinstall the ller panel, do the following:
1. Place the ller panel in the correct location.
2. Reset each push-pin by holding each by the outer
circle while pushing up on the pin assembly from
below. The center portion of the push-pin should
now be above the outer circle.
3. After placing each push-pin into the opening, press
down on the outer circle until it is seated against
the surface of the ller panel.
4. Lock each push-pin in place by pressing the center
of each down until it is level with the outer circle.
Use care not to press down so far that the push-pin
releases again.
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