Your car’s headlights provide you with illumination for driving in low-light situations – fog, rain, snow, and at night, for instance. They also provide visibility for oncoming drivers and pedestrians. They’re vital for safety while on the road. However, they can only do their job if they are properly adjusted.
Headlights are designed so that they can be adjusted – up, down, and side to side. This is to account for things that can throw your adjustment off, such as impacts and collisions. When a headlight is off, it’s easy to tell – the beam doesn’t go where it should, and you find that your night driving suffers. It could even blind other drivers if the headlight has moved upward rather than right, left, or down.
However, adjusting and aiming your headlights is not necessarily a simple matter, and you’ll need to know a thing or two before you attempt it. In our guide below, we’ll walk through some of the tips and tactics you’ll need to know in order to get your headlights positioned correctly.
Why Are Your Headlights Out of Alignment?
Before we explore how to fix the alignment issue, it’s important to understand how misalignment happens in the first place. Some causes are obvious – a front end collision will likely throw your lights out of alignment. A shopping cart colliding with a lens could also do the same thing. However, your headlights can also change alignment over time on their own.
Vibrations caused by driving can cause your lights to move imperceptibly. After a couple of years, they could be in a very different position than when you purchased the car. Even something as simple as installing a new headlight bulb can cause misalignment, particularly if you have a model that requires the removal of the entire headlight lens to get at the bulb.
So, misalignment can be the result of physical impact, but also happens for many other reasons. The key is being able to do something about it. Here’s what you need to do.
There are many reasons that your headlights might not be shining correctly that have nothing to do with the alignment. For instance, if one of your tires is low on air, it will throw the alignment of the entire vehicle off. If you are carrying a lot of weight in the trunk, it will also raise the front of the car. A blown shock or strut will cause that corner of the car to sink, throwing off your headlight aim, as well.
Pop the Hood
First, open the hood of your car. Look at your headlight lens assemblies. You’re checking to see if you have built-in levels or not. Most cars do not, but some do, particularly higher-end vehicles. They will look like a conventional bubble level used in construction and home remodeling, and there should be two per light (one for horizontal aiming, and one for vertical adjustment).
If you have bubble levels, you can simply use the appropriate tool to turn the adjustment screw. In most cases, this is a Torx bit or a star bit. However, you might luck out and have Phillips head adjusters. Some car’s use metric bolt heads, so you’ll need a ratchet and socket. Simply turn the adjuster until the bubble lines up with the center point in the level. Repeat for the second level and you’re done.
Don’t see any bubble levels? Don’t despair. You can still adjust your headlights.
Find a Wall
If your car is like most, you have no bubble levels. That means you’ll need a bit of help with adjusting and aiming. Find a wall that you can park in front of. Your garage door will work in a pinch. The area in front needs to be completely flat, as you’ll need to make sure your car is as level as you can make it. You’ll need to:
- Fill your fuel tank
- Check that all four tires are correctly inflated
- Someone is sitting in the driver’s seat
- Settle the suspension by pushing down on all four corners of the car several times
Park close to the wall. Have someone sit in the driver seat and turn on the lights. With a tape measure, check the distance from the bottom of each headlight to the ground. These should be within a half-inch of each other. If there is significantly more distance, then your issue could be suspension-related, rather than a headlight alignment problem.
With the low beams on, find the centers of the light beams on the wall. Mark both the vertical and the horizontal with a straight piece of tape. You should have two horizontal pieces (top and bottom) and one vertical (center).
Now, park the car about 25 feet from the wall/garage door that you will be using. Note that different automakers have very different requirements here, so check your owner’s manual. Find a way to block one headlight, and then look at how the other one falls on the wall. Compare it to the tape marks you made previously – you should see the brightest part of the beam lined up with or just under the center line mark for vertical measurements, and to the right of the vertical market for horizontal measurements.
If the aim is off, find the adjuster screws on the back of your light housings and adjust the lights until they line up correctly with the tape marks you made initially. It’s best to start with quarter-inch turns of the adjustment screw so you can slowly fine tune the aim.
There you have it – a simple, although somewhat time-consuming method of adjusting and aligning your headlights.