What to Do When the Windshield Fogs Up on the Outside with AC On?
2 Answers
Fogging on the vehicle's glass is caused by the significant temperature difference between the interior and exterior in the current environment. Below are related explanations for glass fogging: 1. Front Windshield: Generally, the front windshield defrosting function is used to treat the front windshield based on the driving environment. If the vehicle is equipped with automatic air conditioning and allows selection of air vent positions, it is recommended to choose the front windshield and central air vent positions, and turn on the rear windshield heating function. This way, the temperature inside the vehicle is constantly regulated, preventing fogging. 2. Slightly Open the Window: If it's not possible to select two directions for air venting simultaneously, turn on the front windshield defrosting function and the rear windshield heating function. If the side windows fog up, slightly opening the window can quickly remove the fog. After closing the window and allowing the interior temperature to rise, fogging will no longer occur.
I've encountered the issue of windshield fogging up on the outside several times while driving, especially when using the AC in summer. Setting the air conditioning temperature too low causes the glass surface to become too cold, making the hot outside air condense into fog upon contact, which is dangerous as it obstructs visibility. My approach is to immediately adjust the AC vents to the windshield-defrost mode, which helps clear the fog; at the same time, I slightly increase the temperature to reduce the temperature difference. If the fog doesn't clear, I use the windshield wipers to temporarily remove it; if that still doesn't work, I check if the recirculation mode is on and turn it off to improve air circulation. For regular maintenance, I recommend cleaning the windshield surface and using glass cleaner to prevent oil buildup that can cause fogging. Remember, safety is the top priority—if the fog is too thick to see through, pull over slowly and deal with it. Regularly checking the wipers and AC system for issues can also prevent this problem, avoiding last-minute troubles.
