You can adjust most headlights yourself in 15 minutes with basic tools
Headlight adjustment is a job you can do in your driveway without special equipment. Most vehicles have adjustment screws or bolts behind the headlight assembly — usually accessible from inside the engine bay — that let you move the beam up, down, left, and right. The process takes about 15 minutes per headlight and requires only a Phillips or flathead screwdriver, depending on your vehicle.
Misaligned headlights are common after a collision, after replacing a headlight assembly, or straightforward from normal wear. Lights that point too high blind oncoming drivers. Lights that point too low reduce your own visibility. Getting them right improves safety for you and everyone else on the road.
Key Takeaways
- Most headlight adjusters are screws or bolts located behind the headlight housing, accessible from the engine bay without removing the light itself.
- Vertical adjustment screws move the beam up and down; horizontal screws move it left and right — your owner's manual shows which is which for your model.
- The wall method (parking 25 feet from a wall and marking the beam height) is the most practical way to check alignment without a shop's alignment machine.
- If the adjustment screws are stripped, seized, or missing, the headlight housing itself may need replacement rather than adjustment.
Locate the adjustment screws in your engine bay
Open your hood and look directly behind the headlight assembly you want to adjust. You will see either two or three screws or bolts protruding from the back of the housing. One screw controls vertical movement (up and down), one controls horizontal movement (left and right), and some vehicles have a third for fine-tuning. Check your owner's manual to identify which screw does what — the layout varies by manufacturer.
If you cannot see the screws clearly, you may need to remove a plastic cover or trim piece. These are usually held by one or two clips or screws and pull straight out. Do not force anything; if it does not come free easily, check the manual for the correct removal sequence. Some vehicles require you to access the adjusters from inside the vehicle, behind the dashboard, rather than from the engine bay — your manual will specify this.
Set up a reference point to measure beam height
Park your car on level ground about 25 feet from a flat wall or garage door, with the headlights pointing straight at it. Turn on the low-beam headlights (not high beam). The light pattern on the wall will show you exactly where your beam is pointing right now.
Mark the center of each beam with a piece of tape or chalk on the wall. The beam should form a horizontal line across the wall at roughly the height of your headlight, or slightly below it. If the beam is noticeably higher or lower, or if it is tilted to one side, you have found your adjustment target. Take a photo of the beam pattern before you start — it makes it easier to see the change as you adjust.
Adjust the vertical screws first
Start with the screw that controls up-and-down movement. Turn it clockwise to raise the beam, counterclockwise to lower it. Make small adjustments — a quarter turn at a time — and check the wall after each one. The beam should sit at or just below the height of your headlight center.
The goal is to have the beam point slightly downward so it illuminates the road ahead without shining into the eyes of oncoming drivers. If your car is heavily loaded (passengers, cargo), the beam may naturally point higher; in that case, aim for a position that works for normal driving conditions. Once the vertical alignment looks right, move to the horizontal adjustment.
Adjust the horizontal screws to center the beam
The horizontal screw moves the beam left and right. Turn it to center the beam on the wall so it points straight ahead rather than angling toward the shoulder or the center line. Again, make quarter-turn adjustments and check the wall between each one.
The beam should be symmetrical — the left headlight beam should point straight ahead, and the right headlight beam should point straight ahead. If one beam is significantly brighter or dimmer than the other, that is a sign of a failing bulb or internal reflector damage, not a misalignment, and adjustment will not fix it.
Test your adjustment on the road
Drive on a dark, empty road (a quiet residential street works well) and observe how the headlights illuminate the pavement ahead. You should see a clear, even light pattern on the road surface without dark spots or bright spots. The beam should not shine into the trees or sky, and oncoming drivers should not flash their lights at you.
If the adjustment still does not feel right after a road test, return to the wall and make smaller adjustments. Headlight alignment is not a one-time measurement — it is a feel-and-refine process. Once you are satisfied, you are done. Most adjustments hold for years unless the vehicle is in another collision or the headlight assembly is removed and reinstalled.
When to replace the headlight assembly instead
If the adjustment screws are stripped (they spin without moving the light), seized (they will not turn at all), or missing, the headlight housing itself is damaged and adjustment is not possible. In these cases, the entire headlight assembly needs replacement. This is a job you can do yourself on most vehicles — it usually involves removing two or three bolts and unplugging an electrical connector — but the assembly itself costs between $150 and $500 depending on the vehicle and whether you buy OEM (original equipment) or aftermarket parts.
If you have adjusted the screws multiple times and the beam still will not stay in position, or if the housing is cracked or visibly damaged, replacement is the more reliable fix than repeated adjustment. A damaged housing will not hold alignment reliably, and you may find yourself adjusting the same light every few months.
Frequently Asked Questions
Do I need to adjust both headlights at the same time?
No. Adjust one headlight, test it on the road or wall, then move to the other. This lets you compare them and catch any asymmetry. Some vehicles have a master adjustment that affects both lights together — your manual will note this if it applies to your car.
What if I cannot find the adjustment screws?
Check your owner's manual first — some vehicles hide the adjusters behind trim pieces or access them from inside the cabin. If the manual does not help, search online for "[your year/make/model] headlight adjustment" and look for forum posts or YouTube videos from owners of the same vehicle. The adjustment location varies widely.
Can I adjust headlights on a car with LED or HID headlights?
Yes. LED and HID headlights use the same mechanical adjustment screws as halogen lights. The adjustment process is identical. The only difference is that LED and HID lights are more expensive to replace if the housing is damaged, so be extra careful not to force anything.
How often should I check my headlight alignment?
Check alignment after any collision, after replacing a headlight bulb or assembly, or if you notice oncoming drivers flashing their lights at you. Otherwise, once every year or two is reasonable. Alignment does not drift on its own under normal driving conditions.
Will adjusting my headlights affect my warranty?
No. Adjusting the screws behind the headlight housing is a maintenance task, not a modification. It does not void any warranty. If you replace the entire headlight assembly, that may affect warranty coverage on that specific part, depending on your manufacturer's policy.