Daniel Stern Lighting Consultancy and Supply
12/04/2006 01:48 PM
will likely have to do the best you can using a visual method.
To prepare for aiming, the car should have at least 1/2 tank of fuel, weight in the trunk equal to the most frequently carried load (this may be a full trunk, or it may be an empty one, or anything in between), and weight in the driver's seat equivalent to the most frequent driver. All of the tires should be checked when cold to make sure they're at the correct inflation pressure. Jounce each corner of the car firmly (grasp the bumper and push down several times rhythmically) to ensure that the suspension is settled into a normal position.
Find a location that has a vertical wall and enough level ground for the length of the vehicle plus 25 feet (7.5 m). The wall will be used as an aiming screen. You'll need to make marks on the wall, so if it is a wall you're not allowed to deface, use tape. Measure a distance of 25 feet (7.5 m) straight back from the wall, and mark this position on the floor or ground. Align front of the vehicle with this floor mark, and then bring the vehicle straight forward, right up to the wall. Make a mark "V" on the wall directly in front of the center of the vehicle. Good references for the center point include such things as hood ornaments, grille badges and license plate brackets.
Next, make a mark "C" on the wall directly in front of the axis of each lamp. The "axis" is often marked with a dot, cross, bulb type designation or name brand, but if not, it is directly in front of the bulb. There is one axis for each lamp, so a vehicle with four lights will have four axes and a vehicle with two lights will have two, plus any auxiliary fog and/or driving lamps that may be present.
Now, move the vehicle straight back from the wall until the headlamps are aligned with the floor mark. Walk to the wall and make additional marks: Extend the "V" mark with a vertical line downward at least six inches. Next, connect all of the "C" marks with a horizontal line we'll call "H-H". Then, measure downward from each "C" mark that represents the axis of a lamp and place a mark "B" per the following tables.
ECE (European E-code) headlamps
Lamp axis height
Distance to measure
Up to 34.5" (80 cm)
3" (76 mm)
35" to 39" (89-99 cm)
4" (102 mm)
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