What to do if the windshield still fogs up outside after turning on the defroster?
3 Answers
First, turn on the car's air conditioning, adjust it to the hot air setting, activate the external circulation, and direct the air vents toward the front windshield to blow hot air directly onto it, allowing outside air to enter the car. Spray some defogging agent or apply soap to the inside of the glass, which can temporarily prevent fogging in this area.
When the windshield still fogs up outside after turning on the defogger, I first check if the air conditioning temperature is set too low. If the AC temperature is lower than the outside, moisture tends to condense on the exterior glass surface. In this case, I try increasing the AC temperature slightly, which usually helps alleviate the issue. During humid weather, I frequently use the external circulation mode to improve air flow inside the car and minimize excessive temperature differences between inside and outside. When fogging occurs, I immediately use the wipers to remove water droplets, and spraying some washer fluid proves more effective in preventing blurred vision that could compromise driving safety. Remember not to point the air vents directly at the glass, as this can worsen condensation. Regularly check if the wiper blades are worn or dirty, and replace them promptly to maintain strong cleaning performance and reduce similar troubles. If problems arise, stay calm—it's safer to pull over and handle the situation properly.
From driving experience, external fogging after defogging is mostly caused by environmental temperature differences. I adjust the air conditioning temperature and airflow direction, setting appropriate warmth to prevent condensation. Activating the wiper washer instantly clears water marks, while checking if washer fluid is sufficient or adding anti-fog agents to enhance effectiveness. The external circulation mode is highly effective—it balances humidity to prevent fog buildup. If the issue persists, clean the glass coating to remove residual oil films and maintain smoothness. If wipers streak, it may be due to hardened or aged rubber—replacing the blades or DIY silicone oil lubrication can solve this. Ensuring simple, effortless operation keeps focus sharp—safe driving always comes first.
