Why does the car's internal air circulation automatically turn off?

1 Answers
VanHope
07/29/25 10:08am
Car's internal air circulation automatically turns off for safety considerations. Here are the relevant details: 1. Reason: If the internal circulation is kept on for a long time, the oxygen level inside the car cabin will decrease. If the driver stays in a low-oxygen environment for an extended period, it can easily lead to drowsiness (oxygen is crucial for alertness, and pure oxygen can even have a refreshing effect). Therefore, to prevent accidents caused by driver drowsiness due to low oxygen levels in the cabin, many car models automatically deactivate this function after the internal circulation system has been on for a certain period, switching to external circulation to introduce outdoor air and increase the oxygen level inside the car. 2. Suggestion: For cars without an automatic internal/external circulation switching function, it is recommended that drivers periodically activate the internal circulation during long-distance driving for better air quality.
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