The fan switch or temperature switch is responsible for sensing when the engine temperature is too high. When the temperature reaches the set point, the switch will turn on the radiator fan. If the switch is faulty, it may not sense the high engine temperature and won't be able to activate the fan.
2. Faulty Fan Motor
The fan motor is responsible for rotating the fan blades. If the fan motor is faulty or has failed, it won't be able to rotate the fan blades and cool the engine.
3. Broken or Damaged Wiring
The wiring that connects the fan switch and fan motor to the battery may become broken or damaged. If there is no electrical connection between the fan switch and the motor, the fan will not be able to turn on.
4. Blown Fuse or Relay
A blown fuse or relay in the fan circuit can also prevent the fan from turning on. Check the fuse box and replace any blown fuses. If the relay is faulty, replace it as well.
5. Faulty Coolant Temperature Sensor
The coolant temperature sensor is responsible for providing the engine control unit (ECU) with the engine's coolant temperature. If the sensor is faulty, it will send an incorrect signal to the ECU, which can prevent the fan from turning on.
6. Faulty Radiator Fan Control Module
Some vehicles have a radiator fan control module that is responsible for controlling the operation of the fan. If the control module is faulty, it will not be able to properly control the fan and may prevent it from turning on.
7. Low Coolant Level
If the coolant level is low, it can cause the engine to overheat and the fan to turn on. However, if the coolant level is too low, it may not trigger the temperature switch to turn on the fan.
