
In car air circulation systems, 'A' stands for automatic control of the internal and external circulation, while 'M' represents the external circulation. When the 'A' button is activated, the air conditioning system automatically determines whether to use internal or external circulation based on the quality of the outside air. When the 'M' button is pressed, the car is in internal circulation mode if the light is on, and in external circulation mode if the light is off. The functions of internal and external circulation in a car are different: 1. External circulation function: It primarily serves to ventilate the car, replacing the internal air when it becomes stale. 2. Internal circulation function: When internal circulation is activated, the air inside the car does not exchange with the outside, circulating instead within a closed environment.

I've been driving for decades and encountered many air conditioning issues. Finding the external circulation button is quite simple—it's on the air conditioning control panel, usually marked with an icon of a car outline and an arrow pointing from outside into the car, indicating the intake of fresh outside air. I often use it during long drives, such as when there's an unpleasant odor in the car or when the windows fog up on rainy days; turning on external circulation helps air flow and prevents fogging. However, in city traffic jams, I recommend not using external circulation to avoid inhaling exhaust fumes. The button's location may vary by car—my old car had it on the left side of the center console, while newer models sometimes place it in the touchscreen menu. Remember, the internal circulation is the opposite icon, with an arrow circling inside the car. Keeping this habit makes driving safer and more comfortable.

As a car enthusiast, I've studied the air conditioning systems of various models. The recirculation button is easy to identify - there's usually an icon in the climate control area showing an arrow symbol indicating outside air flowing into the vehicle, which represents the recirculation mode. Designs vary significantly between brands, with Japanese cars often using clearly marked buttons while European models might integrate it into multifunction knobs. Personally, I prefer using recirculation mode for ventilation when driving in suburbs or on highways to reduce CO2 buildup inside the cabin. But be careful not to confuse it with ventilation mode - recirculation is an independent switch. New car manuals all have detailed diagrams, so I recommend checking them and developing a habit of regular inspection. In short, experiment with the buttons and get familiar with your beloved car to ensure comfortable driving.

When I first learned to drive, I also couldn't figure out the air conditioning buttons. The symbol for the fresh air mode (outside air circulation) is that icon on the AC panel that looks like wind blowing into the car from outside, with the arrow pointing toward the interior. In daily use, like when the car feels stuffy or there's smoke smell, pressing it brings in fresh air. My first car had this button on the right side of the center console, and I got familiar with it after a few tries. The key is to compare it with the recirculation mode icon – where the arrow circles inside the car, don't mix them up. I often use this function during commutes to stay alert, and it's also handy for preventing fog on rainy days. Just remember this simple tip, and you'll operate it with ease.


