What Causes Ineffective Car Defogging?

[LaBeckett]

First, determine whether it's external fogging. External fogging can usually be wiped away easily. If it persists, try spraying some windshield washer fluid. If it still doesn't clear, consider whether there's an issue with the wiper blades. For frost buildup, you can turn on the heater to blow warm air. Additionally, you can activate the air conditioning in defogging mode with the AC on, which should clear the fog quickly. If it doesn't clear completely, gently wipe the glass with a towel to check for any residue or foreign substances. Below are the functions of a car's air conditioning system: 1. Temperature Regulation: This is the primary function of car air conditioning. In summer, the cooling system produces cold air to lower the cabin temperature; in winter, except for large commercial vehicles that use independent combustion heaters, most vehicles rely on residual heat for warming. 2. Humidity Control: Humidity significantly affects passenger comfort. Cabin humidity should generally be maintained between 30% and 70%. Standard car air conditioning systems do not regulate humidity—only through ventilation or advanced luxury car systems with integrated heating and cooling. 3. Airflow Adjustment: The speed and direction of airflow greatly impact comfort. Direct airflow should be limited to a certain range when the temperature is appropriate, and the speed can be adjusted based on passengers' living environment, age, health, and temperature preferences. 4. Air Purification: Cabin air quality is crucial for comfort.