What do the 'a' and 'm' mean in BMW's air recirculation system?
1 Answers
a stands for automatic mode, where the vehicle determines whether to use internal or external air circulation based on the air quality outside; m stands for manual mode, which requires the driver to manually switch between internal or external circulation according to their needs. Here are some relevant details: 1. When to use internal or external circulation: If the air inside the car is stuffy or stale, you can turn on the external circulation mode for ventilation. However, if the outside air is poor, it's better to use the internal circulation mode. 2. The difference between internal and external circulation: The difference between internal and external circulation lies in whether the air intake is closed. In internal circulation, air flows in a closed environment, meaning you may re-inhale the exhaust you exhale. This method of air exchange isn't very healthy, but internal circulation can be beneficial in certain situations, such as when driving in underground parking lots or sandy areas where the external air is very dirty, as it helps to isolate the car from the polluted outside air. 3. When not to use internal circulation: When driving at high speeds, try not to use internal circulation because the lack of oxygen inside the car can cause the driver to feel fatigued, posing a driving hazard.
