Why Does A Vehicles Headlights Turn Foggy Or Yellow

Traditionally, automobile headlights worked without much issue. In the past, automotive headlights were glass and either worked or didn’t. Today, automotive headlights are made of polycarbonate and can turn yellow or foggy without you noticing it.

When automotive headlights turn yellow or fog up, they pose a threat to other cars, pedestrians, as well as to your family and yourself. In many states, severely yellowed or impaired headlights may lead to a ticket and even license suspension. Car headlights are a serious business and involve real safety issues in the maintenance of your car. Yellowed or foggy lenses reduce visibility for many of the cars on the road today.

WHAT CAUSES AUTOMOTIVE HEADLIGHTS TO FOG UP OR TURN YELLOW?

There are multiple reasons why this can happen.

• Dirt and Chemicals: Over time, a car’s headlight develop an opaque layer of dirt and chemicals over the lenses causing them to look cloudy. This affects the visibility of automotive headlights on the road, which can dim the lights.
• Oxidation: With modern automotive headlights, the polycarbonate lenses become cloudy as a result of exposure to air & the elements. The lens develops microscopic cracks when exposed to UV radiation, which can cause “cloudiness”.
• Water Vapor: Due to high moisture content in the air vapor is created inside the automotive headlight “box”. As the outside air becomes drier, the high moisture air gets trapped inside the headlight. The light coming through the headlight is scattered due to the water vapor and creates patterns. Also, it diffuses the light coming through the polycarbonate lens making it harder to see.
• Road Damage: As you drive down dirt roads or damage roads, small rocks and debris hit the headlight lens. This can also happen driving on any road, but more so on damaged roads. When the debris hit the polycarbonate lens it cause dents and pits.