What to Do When Car Windows Fog Up?
2 Answers
Here are ways to solve the issue of car window fogging: Press the defog button, turn on the air conditioning (A/C) switch, and activate the external circulation to remove fog. Use the air conditioning's dehumidification function to reduce air humidity and eliminate fog. Reduce the temperature difference to prevent window fogging. Apply anti-fog spray to prevent dirt and stains on the windows. Open the windows to allow air convection between the inside and outside of the car, which will reduce the temperature difference and gradually dissipate the fog. Causes of car window fogging: There is a temperature difference between the inside and outside of the car. If the temperatures differ, the surface with the lower temperature will have a lower saturated vapor pressure than the surrounding environment, causing water vapor to condense on the glass surface in tiny droplets, forming fog.
Fogging on the car's exterior glass occurs due to temperature differences between inside and outside, causing moisture condensation. I usually turn on the AC to defog first: set the AC to external circulation, adjust the temperature to cool or medium (not too low to prevent frost), and increase the airflow directed at the windshield—the fog clears in seconds. Remember to turn on the fan to assist and speed up air circulation. If your car has a rear window heating function, press the snowflake button as well. To reduce the chance of fogging, avoid drinking hot beverages or placing wet items in the car before driving. If fog has already formed before heading out, gently wipe it with a soft cloth or use the wipers lightly to avoid scratching the glass. Cold cars in winter mornings are prone to fogging, so turn on the AC to defog while warming up the engine. If fog suddenly appears while driving, don’t panic—slow down, pull over safely, and handle the situation before continuing.
