Often, the aim of the headlights is improper; this can cause blind spots for drivers approaching a car from the front or behind, or hinder visibility on the road. The aim should be checked at least once a year or anytime that a new headlight has been installed or anytime the front-end body work has been done. The adjustment screw is located at the top of each assembly for each headlight; there are nuts for adjusting the vertical axis and another for the horizontal axis. First of all, place the vertical piece of masking tape on the wall parallel to the car centerline and parallel to the centerlines of the two headlights, and, in addition, place one horizontal line of tape for further convenience. The position of the vehicle should be 25 feet away from the fire wall, having a stable position, with a half tank of gasoline, and free from heavy load. For low beam adjustment-move the high-intensity zone 2 inches below the horizontal line-2 inches right from the vertical line using the top screw to raise the beam and the side screw for the left/right adjustment. Thus, the high intensity zone should be adjusted to be below the straight horizontal when high beams are on, still noting that low beams are far more significant in considerations of safety. This means that service providers should align the headlights as soon as possible preferably by a professional.