How to Deal with Fogging on the Outside of Car Side Windows?
4 Answers
Open the windows for cross ventilation. If your car has a sunroof, you can also open it to balance the temperature inside and outside the car, and the fog will quickly disappear on its own. Using cold air to defog is fast and direct. Turn on the car's air conditioning cooling switch, activate the external circulation, and direct the air vents to blow cold air onto the glass. In addition to cold air, turning on the hot air from the air conditioning can also achieve a defogging effect by drying the fog on the windshield, allowing fresh air from outside to enter the car.
I've encountered fogging on the side windows of my car several times. It usually happens when the weather is cold and humid, with low temperatures outside the car and relatively higher temperatures inside, causing moisture to condense into fog on the window surface. As soon as I notice fogging, I quickly turn on the windshield wipers and give it a few swipes, which immediately clears it up. If the fog is severe or the wipers don't work, I turn on the air conditioning system, switch to defogging mode, and direct cold air toward the outside of the window, which is most effective. Also, be aware that high humidity inside the car can worsen fogging. You can open the windows slightly for a few minutes to ventilate, but avoid doing so if it's raining heavily. For prevention, regularly clean the car windows to avoid oil buildup, as keeping the glass smooth can reduce fog formation. Remember, safety comes first—fogging can impair visibility and easily lead to accidents, so always pull over and park safely before dealing with it.
As a new driver, I find it quite frustrating when the side windows fog up, making it impossible to see clearly outside due to the mist. The main causes are high humidity and temperature differences, which are most common on winter mornings. I've tried using the windshield wipers first to clear the fog, and it works surprisingly fast. If the fog doesn't dissipate, I turn on the air conditioning: press the A/C button to activate cooling, adjust the vents to blow air outside the window, and avoid using the heater directly on the window, as it can make the fog worse. For regular maintenance, I clean the windows with glass cleaner to reduce grease buildup. When fogging occurs, don’t panic—slow down to a safe spot before dealing with it. Never try to wipe the window while driving, as it’s very dangerous. For prevention, I always keep a dedicated defogging spray handy; a quick spray can prevent fogging for up to a week.
From a physical perspective, fogging on car windows is a condensation phenomenon caused by high air humidity meeting temperature differences. My experience shows that when the window surface temperature falls below the dew point, water vapor liquefies to form fog. The quickest solution is to physically remove it using wipers; alternatively, activating the air conditioning cooling system can reduce the temperature difference on the external contact surface. Avoid directing warm air from the heater straight at the windows to prevent exacerbating the temperature difference. Additionally, controlling the fan speed and switching to external circulation mode can help balance humidity. Technically, anti-fog agents work by forming a film to reduce condensation, with one application lasting several hours. Extending this principle, regular window coating can also prevent fogging, which is crucial for maintaining clear driving visibility.
