How to Adjust Your Headlights in 12 Easy Steps

• Park your car in front of a flat wall and mark the center points of each light on the wall with tape.
• Pull back 25 feet (7.6 m) to see how your lights relate to the center point of each + sign on the wall.
• Pop the hood and look for adjustment screws on top of each bulb. Adjust these screws as needed until your headlights are correct.
• The lights are correct when the area below the horizontal line is illuminated and the bright spots are centered on the middle of each +.

Setting Up

Make adjustments to get your vehicle to its average weight and height. Start by removing any excess weight you normally don’t carry from the trunk of the car. Also, check your tire pressure to ensure it’s at the manufacturer's recommended levels. If possible, have somebody sit in the driver's seat while you do this and aim for a day when your gas tank is half full.

Park your car on level ground, facing a perfectly vertical wall. You can do this in an indoor garage or at your home if you’ve got a large garage and it’s dark out. Use a spirit level to confirm the wall is more or less flat. Park as close as you can to the wall while still leaving room.

Level the shocks by pushing the corners of the car down. This jolts the suspension and forces the car to level out. Just go to each corner of the vehicle and firmly push down on the body to make your vehicle pop up and down a few inches. Sometimes, when you drive and park your vehicle, the momentum compresses the shocks on one side of your car. You want the lights to be as ideally placed as possible! Alternatively, you can measure the distance to the ground from both headlights to ensure that the suspension itself is level.

Making Your Alignment Grid

Turn the headlights on and mark the centers on the wall. Do not use your high beams or fog lights. Locate the brightest point of light on the wall for each bulb. Use masking or painter’s tape to put two + signs on the wall. Use a spirit level to ensure the horizontal and vertical lines are perfectly straight. You can also measure the distance from the floor to each bulb and then mark those measurements on the wall if you want to be extremely scientific.

Use a spirit level to see if the + signs are on the same horizontal plane. Place a spirit level between the two marked center lines to see if they are even. If they are not even, use a tape measure to measure how far up the wall the lower mark is and lower the other center line marker to the same height. These center lines should be no higher than 3.5 feet (1.1 m) from the ground. If your two lights aren’t even, measure the distance from the ground to your bulb. Then, transfer that measurement to the wall to figure out which + sign is too high or too low. Redo that + sign.

Back your car exactly 25 ft (7.6 m) from the wall. Don't estimate the distance! Use a tape measure to make sure you are the proper distance away from the wall. This is the distance your headlights should normally extend to. Always defer to the specs in the owner's manual—some manufacturers recommend different distances for proper adjustment, although 25 feet (7.6 m) is the most common distance.

Adjusting the Lights

Turn the headlights on and assess where the light sits on the wall. Those two + signs you put on the wall aren’t just for show. The brightest point should be the center of each +, and only the area below the middle horizontal lines should be illuminated. If the brightest points aren’t the center of each +, you need to adjust your lights horizontally. If the area above the horizontal line on each + is illuminated, you need to lower the lights. If the light is super low, they need to be raised. If your lights are too high, they can blind other drivers. If they’re too low, you won’t be able to see pedestrians and other cars in time to prevent accidents.

Locate the adjusting screws on the housing for each light. The exact location of each screw will differ from make and model to make and model, although every model works basically the same way—one screw is for up/down adjustments and the other screw is for left/right. You use a screwdriver to manually adjust the angle of the bulb. You usually have to pop the hood to access the bolts on the inside of the engine bay. In some vehicles, you just pop a flange off the rim of the light to expose the screws on the outside. Some cars may feature adjustment bolts rather than screws. On Hondas specifically, there is a bubble level on each headlight casing to help you confirm your lights are correct. You shouldn’t have to remove the light, but you may need to remove a coolant tank, cover, or panel to access the headlight casing. Refer to your manual for more info.

Block one headlight so you can focus on adjusting the other. Put a sheet of cardboard or a chair with a coat on the back in front of one light while you adjust the other. This way, the light from the other light won’t bleed into the headlight you’re adjusting. If you have a have a helper to sit in the driver's seat while you do the adjustments, now is the time to ask them to hop in the vehicle.

Turn the upper screw or bolt to adjust the vertical field. Clockwise usually raises the lights, while counterclockwise turns should lower them. Use a screwdriver and some good old-fashioned trial and error to change the height of the light. Move the bulb until the area directly below the horizontal line on your + sign is illuminated. The top of the most intense part of the beam should be even with, or just below the center of the line of tape you made. This way, you can see ahead while you drive without blinding other drivers.

Adjust the other set of screws or bolts to make horizontal adjustments. Use the same screwdriver to make adjustments to the second screw, if necessary. Move the headlights horizontally until the most intense portion of the headlight beam is hitting the vertical bar on the + sign on the wall.

Test your alignment by driving the vehicle on a safe, quiet road. Since you aren’t sure the lights are perfect just yet, drive slow on a street that won’t have any pedestrians or traffic (an alley is ideal). Make any additional adjustments by repeating the process again until your lights are correct. If your lights “feel” off, they probably are. You should be able to see slightly beyond 25 feet (7.6 m), which is 3-4 car lengths. Do this at night! You aren’t going to be able to see whether your lights are correct or not during the day.