Why Does the Passenger Side Window Fog Up?
2 Answers
Window fogging occurs due to a simple reason: the temperature difference between the inside and outside of the car. Here are some solutions: 1. Utilize the air conditioning: While driving, you can first turn on the cooling function. For a more thorough solution, it's best to turn on the heating either before driving or when parked by the roadside until all fog disappears. 2. Open windows for air circulation: Based on the principle of fog formation, you don't even need to use the air conditioning. Simply opening the windows slightly on both sides allows air inside the car to circulate. This method helps equalize the temperature inside and outside the car, preventing fog from forming. 3. Purchase specialized anti-fog products: Anti-fog sprays can be applied to the inside of the windshield and wiped evenly. There are also special anti-fog towels available on the market, in both dry and wet varieties. These towels are more convenient than sprays, requiring just a wipe, but their effects are shorter, usually lasting no more than 24 hours.
That time I took my family on a long-distance trip by car, the passenger side window kept fogging up, which was really annoying. The main reason was the temperature difference between inside and outside the car. The air inside was warm and humid due to people breathing or sweating, increasing moisture levels. When this moist air met the cold glass, it condensed into fog. That day, the air conditioning wasn't set properly—only the heater was on without activating the cooling function, and the ventilation wasn't fast enough. Plus, the window was a bit dirty, making it easier for fog to accumulate. I tried wiping it by hand, but the fog quickly returned, obstructing my view, which was quite dangerous when driving on the highway. After returning, I learned to set the air conditioning correctly, switching to the external circulation mode or slightly opening the window for ventilation, which significantly reduced the fogging issue. Regularly cleaning the windows and avoiding oil stains or dust buildup also helps a lot.