Why does the fan keep running after the car key is removed?
2 Answers
It is normal for the fan to continue running after the car key is removed, and it usually stops after a few minutes. Here are the detailed explanations: 1. The fan is the cooling fan, and its main function is to blow air for cooling. In other words, as long as the temperature is too high, the fan will operate. 2. There is a sensor near the radiator. When the engine temperature is higher than the set value, the fan will operate; when the engine temperature is lower than the set value, the fan will automatically stop. 3. The fan is not controlled by the key. The cooling fan is directly connected to the battery, so as long as the battery has power and the engine temperature is high, it will continue to run until the temperature drops.
As an automotive repair enthusiast, I often encounter friends asking similar questions. This could be because the cooling fan relay in the vehicle is stuck, causing the fan to continue running after the key is removed; or the temperature sensor is faulty, making the fan mistakenly think the engine is still hot and thus not stopping. A malfunction in the control module could also trigger this issue. If not addressed promptly, the fan will drain the battery, potentially making it difficult or even impossible to start the car next time. I recommend immediately turning off the engine to check the fan relay—lightly tapping it with a small hammer to see if it resets. If that doesn’t work, take it to a professional repair shop for further diagnosis to prevent prolonged damage to the wiring. Additionally, this phenomenon is more common during high summer temperatures, so it’s important to ensure the cooling system is functioning properly.
