Many car owners left their cars outside all night, and when they woke up the next morning, water droplets appeared inside the headlights. In this case, is the headlight flooded? In fact, the problem may not be as serious as thought.
There are two reasons why headlights produce fog:
Large temperature differences in winter cause condensation inside the headlights
In the structure of the qiche headlight, there is a ventilation pipe connected to the outside world. Its purpose is to increase the temperature after the headlight is turned on, and discharge the expanding gas inside the headlight through the ventilation pipe. After the headlight is extinguished, the temperature decreases, the internal pressure difference becomes larger, and outside air is sucked in through the ventilator. During this breathing process, humid air will be inhaled, causing the headlights to condense into fog. Doesn't the manufacturer know about this vulnerability? Of course, the manufacturer understands the disadvantages. In order to prevent moisture and dust from entering the interior of the headlights, a "drying filter element" is installed in the ventilation duct for filtration. Its just that if you operate in a humid environment with large temperature differences for a long time, the effect of drying the filter element will be compromised, and the probability of humid air entering the headlights will increase, which is not surprising, causing headlight fog.
Mist is likely to form after heavy rain or car washing
Careful car owners may notice that fog may appear inside the headlights after heavy rain or car washing. What is the reason? Car owners can analyze this point based on the above points. There is also a sealing problem in the headlights, especially for models older than 78 years. The headlight sealing strips may lose their activity, and the possibility of moist air entering is relatively high, causing There's a good chance there's fog in the headlights.
In addition to the sealing strip, the plastic shell will also absorb moisture in the air like a sponge after being heated. Of course, the effect is not intuitive.
So how to solve the problem of foggy headlights?
Most car owners are not interested in the cause of headlight fogging. They just want to know how to solve it. In fact, the method is not difficult. Under normal circumstances, as long as the headlights are used normally, the temperature generated by the headlights is used to vaporize the water, and the circulation of the vent holes is used to naturally dry the water vapor inside the headlights. If the fog inside the headlight is serious, the car owner can disassemble the back cover of the headlight and dry the headlight. It is recommended to dry naturally. Forced drying will speed up the loss of activity of the sealing strip.
In addition, in a few cases, the headlights are not tightly sealed. In this case, car owners should repair them in time. Otherwise, if it is serious, they can only replace the headlights.
