Fogging is an issue that affects all headlights despite price tag or material. It’s a common myth that more expensive headlights will decrease the amount of fogging. In reality, this could not be further from the truth. Fogging is physical phenomenon that takes place in every light and by no means is it a defect in the product. Think for a moment about times when your windshield fogs up in your car. You simply have to dehumidify it and get rid of the moisture. You can think of the fogging in a headlight to be a similar situation.
Did fogging occur right after your install? If you experience fogging right after you installed a set of lights, there is a good chance that the install occurred in a place or at a time when there was more moisture in the air than normal. It’s common that when lights are installed in the morning or before or after a recent rain, the headlights end up fogging. Ideally, you want to make your install during a very dry day or in a controlled environment.
There is a simple solution however, if you do still find yourself with a bit of fogging. That simple solution is a blow dryer. A blow dryer can be a great way to take care of any extra moisture found within the light housing. One thing to be careful of, however, is that the temperature of some blow dryers can be very high and you want to make sure that you don’t burn yourself or melt any of the plastic housing on the headlight. To utilize this tool effectively, you need to move the blow dryer around aiming through the back of the light toward the internals of the headlight. You want to be very thorough here. You need to make sure the headlight is completely dry of moisture or the fogging will continue to come back. One surefire way to check this, is to shake the housing. If you see any water, this means there is more moisture hiding in there. Continue to blow dry until moisture has been completely removed.
Once you have gotten the housing completely dry, allow it to equalize. When re-installing into your car, make sure all the breather vents on the back of the headlight are pointing down. (This is so that no water collects back up.) All quality headlights have breather vents, so make sure you put the back cover on properly. If the back wasn’t on properly before, this could be the reason for your issue in the first place. Use this opportunity to make sure your install is correct, and you will thank yourself later.
Another important note is that headlights are not meant to be sealed tight. Do not attempt to silicone all the vents or gaps you see. This is almost a guarantee that the headlights will fog up. Your headlights are designed to have those vents breathe and equalize with the air. The basic goal is to not allow large streams of water from rain to get into the housing. For this, you need to make sure the back covers are closed tightly and sealed shut. If you succeeded in eliminating the moisture, than you problem will be solved.