Three Common Causes Of Foggy Headlights

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Have you noticed that your car's headlights become duller with time? For example, they may become yellowish or give off diffused light that cannot illuminate the road properly. Well, yours aren't the only headlamps going down that route. This happens because of different factors including these three:


The primary cause of the yellowing of the headlights is due to the oxidation of the polycarbonate lens. The oxidation is accelerated by the ultraviolet radiation from the sun. Therefore, it is the action of the sunlight and air (oxygen) that clouds the headlights.

The best way to prevent this is to store your car away from the sun to reduce its exposure to UV rays. Since this may not always be possible, there are also protective coatings that may reduce the rate of oxidation. Just be careful with such products so as not to reduce your headlights' illumination. A recommendation from a trusted mechanic is best.

Water Vapor

This happens when the headlights trap air with high moisture content.  If the outside air temperature falls and the headlamps also cool, then the moisture condenses on the insides of the lenses. The scattering reduces the glow or strength of the headlights, making them duller than they were before.

Usually, this doesn't cause serious problems because the headlights' housings are vented. However, if the temperature drops too much, then the water vapor formed may not be vented out of the casings even when they are warmed. In such a case, removing the casing and drying it may solve the problem. While at it, also confirm that the vents aren't clogged with debris.

Dirt and Chemical Accumulation

Your car spews off a lot of chemicals in the form of fluid leaks and exhaust gases. Then there are also chemicals from the tar on the road. These, together with random dirt particles, collect on different parts of your car's body. When the debris accumulates on the headlights, it dims the lights due to the layer's opaque nature. Of course, cleaning your headlights is the best way of clearing the debris and increasing your headlamps' brightness.

The measures outlined above help to keep the headlights bright, but they aren't permanent solutions. Sooner or later your headlights will be too cloudy for safe driving; this is mostly due to oxidation. When that happens, take your car to a professional auto body mechanic so that he or she can sand it and coat it for more brightness.

For more information, contact High Point Body & Paint or a similar company.