How Do You Properly Adjust Your Vehicle's Headlights?

properly-adjust-vehicle-s-headlights Credit: A. Bailey/CC-BY-3.0

To properly adjust your vehicle's headlights, locate the adjusting screws, check the suspension and the centerlines of the headlights. You need a Phillips-head screwdriver and some masking tape for this task. The adjustment must be done after dark and takes about 15 minutes.

  1. Locate the adjusting screws

    The location of the adjusting screws varies depending on the model of your vehicle. They may be on the external rim of the headlight assembly or behind it. Find two screws, one for the vertical adjustment and one for the horizontal, with springs behind them. Some manufacturers no longer provide horizontal adjusters.

  2. Check the vehicle's suspension

    Make sure the tire pressure is right before adjusting the headlights. Bounce the car a few times to settle the suspension.

  3. Check the headlights' centerlines

    Pull your car up very close to a blank wall, such as your garage door. Use the masking tape to mark the horizontal and vertical centerlines of each headlight on the wall.

  4. Back the car up, and turn on the headlights

    Back your car 25 feet away from the blank wall. Turn on the headlights. Check the masking tape marks on the wall to see if the center of the beams match up.

  5. Adjust the headlights

    If the center of the beams do not match the masking tape marks, adjust the headlights until they do. Turn the vertical adjuster clockwise to raise the headlight beam and counter-clockwise to lower it. Turn the horizontal adjuster left or right to move it. Place the center of the horizontal beam 2 to 4 inches below the masking tape centerline mark, and place the center of the vertical beam 2 to 4 inches outside the vertical masking tape mark. This allows your headlights to illuminate the road rather than blinding oncoming drivers.