Visual Headlamp Aiming Procedure (Preferred)

Figures 1

All equipment for testing headlamps must comply with the SAE Recommended Practice For Headlamp Inspection Equipment.

Visual Aiming Equipment - If visual aiming equipment is used, it shall give results equivalent to those obtained using the screen procedure (Figure 1). It shall be in good repair and adjustment, and shall be used in accordance with the manufacturer's instructions. The aiming equipment using a photoelectric cell or cells to determine aim should also have a visual screen upon which the beam pattern is projected proportional to its appearance and aim on a screen at 25 feet. Such visual screen shall be plainly visible to the operator and should have horizontal and vertical referevice lines to permit visual appraisal of the headlamp beam.


Headlamp Aiming By The Screen Method - First, position the vehicle so that it is square with the screen and with the front of the headlamps directly over a reference line which has been painted on the floor.

Next, locate the center line on the aiming screen so that it is in line with the center of the vehicle. This can be done as shown in Figure 1 by sighting through the center of the rear window and over the hood ornament - have vehicle moved or move center line on screen or move whole screen until it is in alignment with these two points.

If there is no center hood ornament, mark the center of the front and rear windows with narrow tape. Use these "sights" to locate the center line of the vehicle.

Aiming Area Required - It is desirable to have a specific aiming area in a darkened location. This should be sufficient for the vehicle and an additional 25 feet measured from face of lamps to the front of the visual screen.

The floor on which the vehicle rests must be flat with the bottom of the screen. If the floor is not level, compensate.

Aiming Screen - If a screen is used, it should be 5' high by 12' wide with a matte white surface well shaded from extraneous light, and properly adjusted to the floor on which the vehicle stands. Provisions may be made for moving the screen so that it can be aligned parallel with the rear axle and so that a horizontal line drawn perpendicularly from the center line of the screen will pass an equal distance midway between the two headings.

The screen shall be provided with a vertical center line, two laterally adjustable vertical tapes and one vertically adjustable horizontal tape.

If a regular commercial aiming screen is not available, the screen may consist of a vertical wall having clear uninterrupted area approximately 6' high by 12' wide. The surface should be finished with a washable non-gloss white paint.

After the aiming screen has been set up in its permanent location, it is necessary to paint a reference line on the floor directly under the lens of the lamps to indicate the proper location of the headlamps when they are being aimed.

IMPORTANT: For each vehicle checked, the horizontal line or tape must be adjusted. Same model and year vehicles will have different standing height for the headlamps.