Foggy or hazy headlights can make cars look neglected and reduce the value of the car. For those that are worse effected, it can even cause you to fail your inspection due to safety concerns. Some people think that because a headlight has become foggy/yellow, they need to buy a new headlight lens.
However, this is not the case whatsoever and you can either choose a headlight restoration kit or even use DIY methods to return the headlight back to their factory finish such as toothpaste or WD40.
Leaving your headlights cloudy decreases visibility during the night as well as distorting the light that does break through. Foggy/yellow headlights look terrible and its worth five minutes of your time to remove the defect.
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What Causes Headlight to Become Hazy and Yellow
Headlights can become cloudy because of four main reasons that are oxidation, road damage, dirt and water vapor. Hazy headlights are less common in newer vehicles but older cars will always eventually suffer from it.
Oxidation of the headlights is the result of the lens being exposed to UV rays that cause the clear coat to crack or fade. Strong chemicals used in cleaning products can do more damage to the clear coat that thins out the clear coat. Usually a compound for oxidation can cut back the hazy headlights to an almost new look and feel.
Road Damage is usually unavoidable, a stone could flick up from the car in front of you at any given point. Sadly, the debris can cause chips and pits on the lens, which breaks the clear coat and leaves it exposed to elements.
Dirt can build up on your cars headlights that attacks the clear coat the longer its present on the lens. Not only that, the build up can reduce the light that is emitted from your bulb through the headlight. Proper car washing on a regular basis can reduce the dirt build up.
Water Vapor is built up inside the headlight from moisture entering someway or another. Usually after changing car headlight bulbs, many people will not secure the rear of the headlight properly, allowing moisture to enter. This can give the effect of the headlight looking cloudy but luckily it is not permanent.
The above are just the usual causes but there are many other reasons. One cause that resulted in hazy headlights were previous tinted headlights where film was glued onto the headlight. Once removed, there was glue residue as well as damage to the clear coat.
How to Fix Foggy and Hazy Headlights
As you search for cars to buy at car dealerships and online, you will notice some with hazy headlights. The seller of these cars are losing money for a simple 5 minute fix that anybody can carry out even with household products. There are many different products and methods used for the fix, but I strongly recommend a cutting polish or toothpaste.
Clean Hazy Headlight using a Cutting Compound
For the avid detailers, using a combination of a polishing machine and abrasive cutting compound is the best method. I have seen car owners use sandpaper with a 2500-grit rating and personally I have never needed to go to this extent.
The correct abrasive cutting polish used with a rotary polishing machine has provided excellent results every time. Using the following steps with a rotary machine polisher on foggy MK5 golf headlight gave the following results.
The process used for cleaning hazy headlights with a polish cleaner:
- Thoroughly clean and then dry the headlight
- Protect surrounding areas with detailing masking tape
- Pour blobs of cutting compound to the buffer
- With the buffer off, rub the headlight with the buffer to spread polish
- Use the polishing machine to work the compound into the headlight
- Gradually speed up the machine
- Buff off the polish residue
- Repeat if there were any areas missed on the headlight
To extend the lifetime of the headlight, I would recommend that you apply wax onto the headlights. Using this approach to clean foggy headlights is highly effective and relatively quick.
Clean Hazy Headlights using Toothpaste
Toothpaste main purpose is too clean teeth but have you seen what it can do to headlights? Toothpaste is a light abrasive and acts in a similar way to a cutting compound by removing a small layer of clear coat. We strongly advise not to use toothpaste that contains extra crystals and what not. Stick to a normal plain toothpaste with no additives, which is completely smooth. Otherwise you could end up scratching your headlight which defeats the purpose of cleaning them.
To remove yellowness and foggy headlights, use the following steps:
- Clean the headlight and remove any dirt
- Protect the surrounding ares with masking tape
- Add water and dampen a soft cloth
- Add a moderate blob of toothpaste to cloth
- Rub toothpaste in circular motion with pressure into the headlight
- Continue to rub for 5-10 minutes for full effect
- Clean and rinse the cloth
- Rub the toothpaste residue from the headlight
- Allow to dry and pat yourself on your back for a great result
The toothpaste method is used by many car owners and is highly effective. To prevent repeating this process every 6 months, we strongly recommend applying car wax that acts as a protective layer that prevents future damage.
Another product that you can use instead of toothpaste is bug repellent. However the most popular household product to clean headlights certainly is the mighty toothpaste.
How to Prevent Hazy Headlights
As mentioned at the end of both of removal methods, car wax is the best form of protection. The wax builds a protective layer against UV Rays as well as dirt. Another less obvious method is to park the opposite direction to the sun. This is a more direct approach at avoiding direct UV rays attacking your headlights.
There are also many plastic films that will provide a long term solution to protecting headlight. The films are designed to take extreme damage from UV rays and dirt without effecting the headlight that it is protecting. Lamin-X are the leaders in this market and they have an offering of many different colors. Lamin-X also offer protective plastics films for fog lights and rear light as well for an all round protection.