Aiming Area Preparation

Choose an appropriate aiming area, then prepare the aiming screen as described in the following.

• The aiming area should be darkened and large enough to accommodate the vehicle and an additional 7.62 m (25 ft) measured from the face of the headlamp capsules to the front of the screen.
• The floor on which the vehicle rests must be flat with the bottom of the screen. If the floor is not level, compensate as necessary.
• The aiming screen should be at least 1.52 m (5 ft) high by 3.66 m (12 ft) wide with a matte white surface well shaded from extraneous light, and properly adjusted to the floor on which the vehicle stands. The screen should be provided with a vertical centerline (3), 2 laterally adjustable vertical tapes (2), and 1 vertically adjustable horizontal tape (1).
  Fig 1: Preparing Aiming Area

  Courtesy of GENERAL MOTORS CORP.

  Important:  For each vehicle checked, the horizontal line or tape (1) on the screen must be adjusted. Vehicles of the same model and year may have different standing height for the headlamp capsules.

• Make provisions to allow the screen to be movable, so that it can be aligned parallel with the rear axle of the vehicle. This will allow for a horizontal line drawn perpendicular to the centerline of the screen to pass through the center point between the 2 headlamp capsules (4).
• After the aiming screen has been set up in a permanent location, paint or tape a reference line on the floor 7.62 m (25 ft) from the screen, to identify the proper location of the headlamp capsules when they are being aimed (5).

  If a regular commercial aiming screen is not available, the screen may consist of a vertical wall having a clear uninterrupted area at least 1.83 m (6 ft) high by 3.66 m (12 ft) wide, finished with a washable non-gloss white paint.