To align headlamps, first park the vehicle on a flat surface 2 to 3 feet in front of a solid object such as a wall or fence. Turn on the headlamps, and mark the center of the beam with a cross. Back the vehicle up 10 to 25 feet. If the beams do not shine directly on the marks, loosen or tighten the screws on either side of the headlamps until they do.
Headlamps feature both vertical and horizontal adjusters. Vertical adjusters are located at the bottom of the headlamp housing and often require the removal of the battery or coolant reservoir to access them. Horizontal adjusters are sometimes located on the outer rim of the headlamp, but due to the increasing popularity of halogen bulbs, they are now typically found on the back of the assembly or eliminated entirely.
If the headlamp needs adjusting, do so by turning the adjusters a quarter-turn at a time. Examine the beam's relation to the markers for confirmation. Pay close attention to the most intense part of the headlamp's beam, particularly on the vertical setting. Poorly adjusted headlamps can make it hard for approaching motorists to see. As a courtesy to other drivers, aim the most intense portion of the beam 2 to 4 inches to the right of the vertical center.