A little fog appears inside the car headlights, which is something most car owners have encountered. But in most cases, it is just a layer of mist. After turning on the lights, the mist disappears within three to five minutes. It does not have much impact on driving, so most car owners do not pay attention.
Of course, some car owners think that such headlights have quality problems. Actually, to be honest, that's not entirely true.
Anyone who has studied junior high school physics knows the principle of thermal expansion and contraction. When the car headlights are turned on, they are converted into light through electric heating, and a lot of the heat energy cannot be dissipated in the car lights. When the air heating tent expands when heated, it needs an outlet to discharge the excess air. Therefore, a vent pipe will be left in the car headlight design. Feed air in and out of the headlights to maintain a balanced air pressure inside the headlights. As well as maintaining the temperature and stability of the headlights during normal operation.
But often because of this breather tube, a considerable part of the water vapor in the air will enter the inside of the headlight through this breather tube. After the headlights are turned off and cooled down, the temperature drops and adheres to the light wall. When it gathers to a certain extent, it becomes water droplets, and then flows along the lines of the lampshade.
In normal summer and sunny days, there will be no moisture in car headlights because the humidity in the air is not high. However, such problems often occur during the rainy season, autumn and winter. Generally, it is normal for a small amount of water vapor to enter, but if a large amount of water vapor enters, then you need to pay attention.
Of course, there are other reasons. For example, some car owners like to wash their cars by themselves. They wash the headlight shades with a water pipe and watch the dirt and leaves being washed away by the water. It feels very refreshing.
However, most car owners do not do enough cleaning and drying of the water after washing their cars. After the car is started, as the engine temperature rises, water turns into water vapor, increasing the humidity in the engine compartment. This will pose a certain threat to the car's wiring, and some water vapor will also enter the headlights.
Of course, the above are all normal situations, and the design principles cannot be changed. For example, the water mist in the car lights caused by the reasons mentioned above is also unavoidable.
If water enters abnormally (not fogged), there are several possibilities. One is that the car headlights are cracked and damaged abnormally, causing water to enter the headlights. Another is that the sealing strips of the car headlights have aged and have not achieved complete sealing. Both of these are organic lesions that require some repairs.
If the water intrusion is not serious, we can use the baking method to simulate the work of the car headlights by heating the slow air vents on the front of the car headlights to drive out the water vapor, but this process will take half an hour to an hour, which is quite good. What a waste of time. When using this method, you need to be careful not to bake one position alone, otherwise the plastic on the car headlight surface will melt and cause ripples.
Generally, for headlights that are physically damaged, you can try to replace the lens of the lampshade, but the labor cost may be more expensive than the purchase cost of the car lens. If the headlight is not tightly sealed, you can only re-seal the edge of the lampshade.
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