Is It Normal for Headlights to Fog Up After Washing a New Car?
2 Answers
Fogging inside the vehicle's headlights may generally be caused by poor sealing of the headlights or excessively humid storage conditions. Headlight fogging itself: Occurs due to temperature changes and is not significantly related to whether the vehicle is moving or stationary. For example, while driving, continuous airflow cools the headlights, but once the vehicle stops, the lack of airflow to dissipate heat causes the headlight temperature to rise, leading to fogging. Things to note when washing the car: Only clean the surface of the headlight casing, not the back of the headlights. Normally, washing the car should not cause excessive fogging unless the headlights are not sealed properly.
A while ago, I bought a new car and got quite a shock when I saw fog inside the headlights after washing it. However, after asking a few experienced drivers, I learned that this is actually quite common. The main reason is that water vapor enters the headlight housing during washing, and temperature changes cause moisture to condense, forming a thin layer of fog. Modern headlights are designed with tiny ventilation holes to allow air flow and regulate pressure, so this phenomenon is normal during significant temperature variations. Usually, driving with the headlights on for a few minutes generates enough heat from the bulbs to dry out the fog, making it disappear naturally. However, if you notice that the fog persists or becomes severe every time you wash the car, it might indicate damaged sealing strips or clogged drainage holes, and you should promptly visit a workshop for inspection to avoid potential hazards. Don’t take it lightly—regularly checking the headlight seals during maintenance can prevent this minor issue.
