How to Defog the Car?
4 Answers
Methods to defog the car: 1. Open windows for convection: Open the windows to allow air circulation and equalize the temperature inside and outside the car; 2. Air conditioning defogging: Turn on the hot air mode of the air conditioning to evaporate the fog inside the car; 3. Dilute dishwashing liquid with water, dip a clean cloth into the solution, and apply it to the windshield; 4. The use of glass anti-fog agents can reduce condensation on the glass surface caused by moisture and eliminate fog. Fogging on the windshield mainly occurs in winter or during cold rainy seasons when there is a large temperature difference between the inside and outside of the car. The temperature of the windows is very low, and when people sit inside the car, the water vapor they exhale and the external water vapor come into contact with the cold glass, instantly liquefying and forming a layer of fog.
I've been driving for over a decade and have figured out quite a bit about defogging. Fogging inside the car is mainly caused by high temperature and humidity inside the vehicle, especially during winter or rainy days when there's a big temperature difference. The most effective method is to turn on the air conditioning immediately after starting the car, press the defrost button, set the fan to a higher speed directed at the windshield, and also turn on the AC button to help dehumidify. If the fogging isn't severe, opening the windows for a few seconds to ventilate before closing them again works well too. Remember to check if the cabin air filter is dirty, regularly clean the inside of the windows with glass cleaner to avoid oil film buildup that makes fog harder to remove. Safety first—always defog before driving to ensure clear visibility for safe travel.
As a new driver, I used to be a bit flustered when defogging. I tried opening the windows to let air circulate before closing them, which worked but was a bit slow. I found that activating the air conditioning defogging mode is the most reliable—just press the fan-shaped icon button, turn up the airflow, and it clears up in seconds. I also bought defogging spray online for emergencies; after spraying and wiping the glass clean, it stays fog-free, which is quite handy. I heard that wiping windows with soapy water can prevent fogging too—tried it once, but it doesn’t work every time. When humidity is high, avoid snoring or eating hot food in the car, as fog builds up faster. Usually, adjusting the air circulation between inside and outside helps maintain airflow.
As a homemaker, I get particularly nervous about defogging issues—driving with blurred vision is too dangerous. As soon as I notice fog on the windows, I immediately press the defrost button and set the windshield blower to maximum, focusing on the front glass. If there's fog on the rear window, turning on the rear defroster is the easiest solution. Adjusting the air conditioning temperature to near room temperature helps reduce humidity differences. The key to preventing fogging is to clean water and wet items off shoe soles before getting in the car to avoid bringing in moisture. During the rainy season or winter, check the air conditioning system more often to ensure it stays dry. For safety, wait until all the fog is completely cleared before driving—don't risk those few seconds.
