Foggy headlights dimming your view? Moisture trapped inside needs to be fixed before your next vehicle inspection or nighttime driving. There are several ways the moisture could have made its grand entrance, so the proper fix would depend on figuring out how the moisture could have entered.
We will cover every possible entry point so you can dry out your headlights and get your vehicle on the road again.
What Causes Moisture to Get in a Headlight?
There are three main causes of moisture inside of your headlight. All of these can relate to other exterior lights, including fog lights, tail lights, and side markers.
#1. Headlight Vent.
The second possible cause is a moisture vent being blocked. This is the optimal issue because if you play your cards right, you can fix the bike without breaking the seal to repair the headlight.
A moisture vent that is blocked will cause your headlight to fill with water as when the halogen bulb heats up and cools down, it creates condensation, and without somewhere for that condensation to go, you have moisture inside the headlight.
#2. Headlight Seal.
The first potential cause is a defective headlight seal. If this is the case, you can either repair the seal or replace the headlight.
#3. Damage to Headlight.
Finally, you can have a cracked or damaged headlight assembly. If this is the case, you can either get crafty with repairs or, more likely, replace the headlight assembly.
Is Condensation in the Headlight Assembly Bad?
It can be. There are several reasons that condensation in your headlight assembly is bad.
First of all, it’s water around electrical components, which is never good. You can short out the system, corrode wiring, and cause many problems that will require you to get the car fixed because of.
Also, condensation in the headlight leads to foggy headlights. You’re still going to get light when you turn on the headlights, but tons of light will be obstructed by the condensation, which means you won’t get as much visibility. It’s easy to see why this is a big deal.
In many circumstances (most), headlight condensation will naturally go away. Car manufacturers understand that some level of moisture is going to occur, so it should work itself out.
Many manufacturers (like Hyundai) have even issued service bulletins for technicians to leave headlight condensation alone, because it’s normal.
Often, the condensation will disappear once the weather warms up or when you’ve been driving the car with your lights on.
If, however, the condensation does not leave after a day or two, then it’s time to find and fix the actual problem.
How to Get Moisture Out of Headlights?
Here are four approaches to get rid of moisture and condensation in your headlight assemblies. These are just temporary fixes until you can track down and rectify the cause of the issue, which we will cover next.
#1. Compressed Air.
You can use either a can of compressed air or an air compressor with a blowgun.
Always hold the can or blowgun at least 6 inches away from the headlight assembly to avoid pushing it too hard into the bezel, and just aim the stream of compressed air into the headlight where moisture is, and direct the air where there’s the most water.
This method should only be used if you have moderate moisture; too high pressure may rip the seals on your car headlight.
#2. Hairdryer or heat gun.
A heat gun (faster) or a hairdryer (safer) is worth a shot to get rid of the condensation. Just turn on your device of choice and aim it (at a safe distance) at the affected headlight for a couple of minutes to dry the moisture out of the headlight.
The heat will help evaporate the moisture inside the headlight assembly. Just be safe and keep the heat source a respectable distance from the headlight, or you may melt the plastic and/or the seals.
#3. Silica gel packets.
Hmm, not the best method, but it can work too. Grab 1 or 2 silica gel pockets (better yet, save those little packets from your products) and put them inside the headlight assembly.
Leave them overnight or for one full day (don’t drive the car) while they absorb the moisture and leave your headlights dry.
#4. A dehumidifier and fresh air.
If moisture in the headlight is severe, you may consider using the dehumidifier and air approach.
Go put your car in the garage and then place your dehumidifier near your car (level with the affected headlights), then just let it run for several hours or overnight to pull the moisture out of your car headlights.
How to Remove Moisture from Headlights
To remove moisture from your headlights, here are some steps to take:
1. Remove Minor Condensation
If you only see a small area of condensation building in your headlight, there are some simple tricks to successfully remove it without breaking the headlight seal!
It may be relatively easy to break the seal between your headlight lens and headlight housing, but if you manage to break the seal, you will need to be very careful to ensure you have a tight seal once you replace the headlight lens.
If you are uncomfortable working with sealants, it may be worth taking your vehicle into a mechanic who is.
Step 1: Check the vent.
Before you remove the seal, check your headlight housing vent. The placement of the venting on the unit is going to depend on the make and model of your vehicle, but most headlight units will have some sort of venting to combat condensation buildup.
Blocked venting is a very common cause of minor condensation. It could be blocked for any number of reasons, from debris, dust, or even spider webs.
Step 2: Clear the vent.
Carefully wipe the vent or blow it out with air. The vent cap may be removable for proper cleaning.
Be mindful when using compressed air. A little goes a long way, so use minimal pressure so you don’t disturb the headlight bulb or blow out the headlamp seal.
Step 3: Check the bulb seals.
Make sure the light bulbs installed in the housing are sealed properly, and check if the gaskets are not nicked or kinked. If you think the seals may not be good, please replace them.
Note: Try not to blow or push any debris into the headlight housing; otherwise, you will have to break the seal to get it out.
2. Major Condensation Removing
Major condensation removal involves some more involved tricks. There are choices, depending on your personal resources, available time, and amount of condensation. To get rid of major condensation, you will need to remove the headlight unit.
Tools you need:
- Screwdrivers
- Ratchet and socket set
- Desiccants like silica gel packs
- Heat gun
- Lint-free towels
- Silicone
Step 1: Get the headlamp assembly out.
Remove the mounting screws or bolts that mount the headlamp. In some vehicles, all fasteners are easy to find, meaning you can access them easily.
On other vehicles, fasteners are hidden and require taking off other parts like the bumper or grille. Check the service manual instructions specific to your application.
Step 2: Remove the bulbs.
Remove all of the bulbs that are in the housing. Put the bulbs down on a clean, lint-free cloth. Ensure you do not touch the glass of the bulb with your bare fingers.
Step 3: Blow out with hot air.
Use a hairdryer and blow it into the vent or outside of a rigid headlight unit. The hot, dry air should dry out the headlamp as it heats up. The water vapor will push out of the bulb and from all openings. So, give the headlight unit time to cool off to see if this method actually worked.
Step 4: Use a desiccant.
You can also put them in silica gel packs to absorb any remaining moisture. Silica gel can absorb moisture in the air and can be put in the headlight assembly. Just make sure you remove the pack before assembly, and it isn’t bouncing around in front of your beam of light or exposed to bulbs.
Step 5: Wipe out the headlamp assembly.
If you want to know how to get water out of headlights effectively, or if there is mildew or dirt to remove, you need to remove the seal. First, you should look at a service manual to see if the headlamp assembly can be separated from the housing.
If so, this will be much more difficult and require a heat gun unless the assembly has a replaceable seal. If you have no experience with a heat gun in this application, your headlight assembly is not the project to learn about using a heat gun. This assumes you have a replaceable seal.
Remove the seal and clear plastic headlight cover from the housing carefully. Make sure you did not miss the obvious, screw or other attachment point. Wipe off the moisture with the cloth you Wipe the moisture off.
When you wipe with the cloth, make sure it is completely clean and dry. Using a cloth to dry the interior will eliminate the majority of the moisture, but it is not a foolproof solution.
It is time to check again for more moisture or debris in the headlight assembly. Follow the procedure below to seal it up properly and eliminate further moisture. This will be the most vital step, because if you reassemble incorrectly, there will be more moisture allowed in the headlight as a result.
How to Fix Condensation In Headlights
If you’re experiencing condensation in your headlight assembly, you have to get to the bottom of the problem.
There are a few different approaches to this, as it all depends on how the condensation is getting in and just how much condensation you’re dealing with.
Cracked Headlight Assembly
Let’s start with the worst-case scenario, which is a cracked headlight assembly. I’m not talking about a faulty seal or a blocked vent, but about an actual crack. In this situation, you’re going to need to replace the headlight assembly to stop future water from getting in.
In terms of a temporary fix, you could use a hairdryer and dry everything out, but it’s a hit or miss if that works well enough. Even after using a hairdryer, you will most likely see condensation again after the morning dew, rain, or whatever other moisture puts it back to square one again.
Bad Seal
The second problem is a bad seal. This should probably be taken seriously because the seal is not usually something that can just be replaced, in most cases, that is. You’re going to have to remove the headlight assembly and carefully pry apart the assembly at the seal.
First, dry everything off inside. From there, you’re either going to need to get a glue gun and run a new bead around the whole assembly, or if you get lucky, find a seal for the headlight at an auto parts store.
But, many headlights are not the type that have seals, so you’ll likely need to do it on your own. You want an airtight seal, so take your time and do it right the first time.
Blocked Moisture Vent
The third possible problem is that your vent is blocked. That vent escapes any condensation that builds from the fluctuating temperature that the bulb causes. So many pieces of debris can block the vent, so check that it is not blocked first before you remove any seals.
If it’s not, then whatever you can do to clean out the debris in the headlight and not push in. If it gets stuck inside the headlight assembly, then you are back to needing to break the seal to get it cleaned out.
What If Water Is Getting In The Headlight, However?
If you continue to have water get in your headlight after your repairs, the chances are you still have a bad seal or blocked vent. You could either attempt to fix it again or just replace the headlight assembly altogether.
Replacing a headlight assembly is not always cheap, but it’s certainly better than shorting out the system and causing a fire or losing visibility at night and crashing into someone.
Whatever you do, don’t just live with moisture in your headlight assembly. It is just a matter of time before the small inconvenience turns into a big problem.