Which button should be pressed when the rearview mirror fogs up?
3 Answers
To defog the rearview mirror, press the rearview mirror heating function button. The defogging symbol for the rearview mirror is the same as the heating symbol, which is a rectangle with three upward wavy lines inside. The car defogging button can reduce moisture, fog, and frost on the front and rear windshields and the exterior rearview mirror surfaces by heating the electric heating wires embedded behind the mirror. This improves the driver's visibility and ensures the mirror surface remains clear, making driving safer. How to use the rearview mirror heating function: The rearview mirror heating function generally has two activation methods. One is combined with the electric rearview mirror adjustment function button—simply rotate the knob to activate it. The other is located on the air conditioning control panel—press the heating button to activate it. No manual angle adjustment is needed, as there is an adjustment button on the driver's side. Principle of the rearview mirror heating function: After pressing the button, the electric heater behind the rearview mirror glass will quickly heat up to a fixed temperature within a few minutes, usually between 35-60 degrees Celsius. The heat will dissipate from the left and right rearview mirrors. Meanwhile, due to the temperature increase and evaporation, water droplets on the mirror surface will gradually shrink, and fog will slowly disappear, thereby heating the mirror and removing frost. If the rain is particularly heavy, the effect may diminish and become less noticeable. Precautions for using the rearview mirror heating function: The principle of rearview mirror heating involves adding electric heating wires to the rearview mirror, which consume a significant amount of electricity. When using the rearview mirror heating function, ensure the car is in an ignited state. Avoid activating the rearview mirror heating function when the car is stationary to prevent draining the car battery and making it unable to provide sufficient power for starting the car. Other methods to defog the rearview mirror include: Opening windows for air circulation: Crack open the side windows slightly to allow air convection between the inside and outside of the car. This reduces the temperature difference, and the fog will gradually disappear. Adjust the car's air conditioning to the appropriate setting to use the warm air blown by the AC for defogging.
I've encountered the issue of foggy rearview mirrors quite a few times, especially when driving in rainy weather. The combination of rain and temperature differences between the inside and outside of the car easily causes fogging, which affects the safe observation of the rear. I looked around in my car and found that the button on the air conditioning panel with a fan icon and square pattern is specifically for defogging. When pressed, the indicator light turns on, and the fog dissipates after a few minutes. I've also learned some small tricks, such as spraying anti-fog spray in advance or regularly cleaning the mirror surface, which can prevent the problem. If not dealt with promptly, blurred vision can be very dangerous, so I always habitually check whether this button functions properly to ensure safe and worry-free driving.
To address foggy rearview mirrors, as a regular car owner, I usually look for the button with small dots and a square symbol near the air conditioning controls. Pressing it activates the mirror heating function to quickly clear fog. This button is often shared with the rear window defroster, making operation simple—just start the vehicle and press it to take effect. Fog forms due to moisture condensation, and the button works by heating built-in wires to evaporate water droplets. If ineffective, I recommend checking fuses or wiring to prevent minor issues from escalating, while maintaining cabin ventilation helps reduce moisture buildup.
