Driving along one evening it comes to your attention that other drivers are consistently flashing their headlights at you. You don’t know them and you haven’t seen any signs of a speed trap. The other drivers may be trying to let you know your headlights are out of alignment.
Every driver knows from experience that being blinded by another car’s headlights is not only annoying but also dangerous since it results in vision being impaired. Straightening the headlamps out may be a little time consuming, but it is worth the effort.
Most makes and models come equipped with headlight adjusters. Sometimes these adjusters are for vertical aim only. In this situation if the problem is horizontal the job will become a try and check the aim practice in patience. Horizontal imbalances are usually caused by a faulty alignment in the headlight housing of the front end. The only recourse left to you is to adjust the housing, check the alignment, and repeat until the level is acceptable.
Whether trying to adjust headlights vertically or horizontally or both, a bubble level will be your best friend. Here is a quick run down on how to get Betsy’s eyeballs straight. Be sure to park the car on a flat, level surface. If possible have the car face a blank wall, neutral colors like white or gray work best. Avoid any internal light shining on the car.
Another useful tip before you begin the headlight alignment is to make sure the tire pressure is correct. If the tires have too little pressure it will throw off the level of the lights. Once the tires have proper air pressure, the bubble level becomes invaluable. A tape measure will make the process go more smoothly as well. Place the car exactly 25 feet away from the wall you are using to check the lights.
Tools used:
Standard mechanic’s shop tools (wrenches, sockets, ratchets, screwdrivers, etc.)
Drill, drill bits, marker, wood or a wall, 25 mm hole saw, electrical tape, safety goggles, gloves.
Aiming Headlights
Choose a location on level ground in front of a blank wall or garage door and position the vehicle so it’s perpendicular to the wall and about 25 feet back.
A laser-pointing tool can help you align the car and mark the tire locations on the wall for reference.
Measure and mark the distance from the center of one headlight to the center of the other, and also measure the distance from the center of each headlight to the ground.
Use electrical tape to mark the centerline between the tire marks, and then measure half the distance between the headlights on either side of center. Mark a tall vertical light for each headlight.
An alternative method, if you are not sure that the car is perpendicular:
Using your tape measure, find the exact middle of both the windshield & rear window and mark them with strips of tape, creating vertical center lines, front & rear.
Standing behind the car, now sight along those center lines, as if you were lining up sights on a rifle in a carnival shooting gallery. When center lines are aligned, you can locate the headlight centerline on the wall. Mark this with another strip of tape.
Mark those lines at the distance you measured between the headlights and the ground on the car, and run a horizontal line across the marks.
Turn the headlights on low and see how they look. For a car with halogen bulbs, you would want the beams to be centered on the crossbars, but since the HIDs are so powerful, it’s preferable to be just below the mark.
If the lights need to be adjusted, open the hood and locate the vertical and horizontal adjustment screws on the headlight housings.
Adjust the lights until they line up correctly, and you’re good to go.
Note: This method will give you an approximate adjustment. To have your headlights aligned precisely, take your car to an auto service center.