What Causes the Car Fan to Keep Running?
2 Answers
The reasons why the car fan keeps running: 1. Loose circuit connection: You can try unplugging the fan's wiring harness and performing a separate power-off treatment; 2. Damaged water temperature sensor or stuck fan relay contacts: For such issues, simply replace them with new ones at a repair shop. The car fan is installed behind the radiator. When activated, it pulls air from the front of the radiator. However, some models have the fan mounted in front of the radiator, blowing air toward it. The fan starts and stops automatically based on the water temperature. At high speeds, the air pressure difference between the front and rear of the vehicle is sufficient to maintain the water temperature at a certain level, allowing the fan to remain inactive.
If your car's fan keeps running non-stop, I think it most likely indicates an issue with the cooling system. The most common scenario is that the engine temperature is too high, triggering the fan to run continuously for heat dissipation. This could be due to insufficient coolant or a leak, resulting in poor heat dissipation; or the thermostat might be stuck and unable to properly regulate the water temperature. A faulty sensor could also misjudge the temperature, causing the fan to start erroneously. Additionally, if you have the air conditioning on, it's normal for the fan to run frequently to help cool the condenser. But if this happens without the AC on, you should be alert. Wiring or relay problems can also cause the fan to run uncontrollably. I recommend first checking the coolant level and color, testing the sensor for accuracy, and if necessary, visiting a repair shop for diagnosis. If not addressed promptly, excessive fan wear or engine overheating could lead to more significant damage—safety comes first.
