Buick CENTURY 1999 Owner's Manual page 263

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:
D
The vehicle must have all four tires on a perfectly
level surface.
D
If necessary, pads may be used on an uneven surface.
D
The vehicle should not have any snow, ice or mud
attached to it.
D
The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being done.
D
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.
D
Close all doors.
D
Tires should be properly inflated.
D
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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