What Causes the Electric Fan Motor to Make Noise but Not Rotate?
3 Answers
There are several reasons why a car's electric fan does not rotate, including the coolant temperature not reaching the required level, relay failure, or issues with the temperature control switch. Long-term lack of lubrication: Electric fan control methods: Unlike engine-driven fans, car electric fans need to adjust their operating status based on the coolant temperature. Some are controlled by the vehicle's ECU, while others use a thermistor switch. Different cars have different electric fan control methods. Structure: Generally, the electric fan assembly includes the electric fan, bracket, temperature sensor, temperature control switch, relay, wiring harness, etc. If the car's electric fan is not rotating, you can troubleshoot based on the above factors. Components: The engine consists of five major systems: cooling, lubrication, ignition, fuel supply, and starting systems. Main components include the cylinder block, cylinder head, piston, piston pin, connecting rod, crankshaft, flywheel, etc. The working chamber of a reciprocating piston internal combustion engine is called the cylinder, and the inner surface of the cylinder is cylindrical. The piston, which moves reciprocally within the cylinder, is connected to one end of the connecting rod via the piston pin, while the other end of the connecting rod is linked to the crankshaft. The crankshaft is supported by bearings on the cylinder block and can rotate within the bearings, forming the crank-connecting rod mechanism.
In my experience, there are several common reasons why an electric fan motor makes noise but doesn't rotate. It could be due to aging bearings lacking lubrication, which dry out and seize up over time, causing the motor to only hum without turning. I've encountered this many times - try gently rotating the blades; if they move, it's a lubrication issue that can be fixed by adding some machine oil or lubricant. Another possibility is that the fan blades are jammed by dust or foreign objects, requiring power-off cleaning of both the protective grille and blade area. Lack of regular cleaning often leads to this, especially during dusty summer months, making periodic maintenance crucial. Additionally, internal rust or wear in the motor can also cause this - if inspection shows irreparable damage, consider replacing components. Regular cleaning prevents most fan malfunctions.
As someone who has repaired household appliances, I believe that when a motor makes noise but doesn't rotate, it's mostly an electrical issue. For example, a faulty starting capacitor may fail to provide sufficient current to start the motor. If the capacitor is bulging or has failed, it needs to be replaced. Alternatively, a short circuit in the winding can cause the motor to heat up internally without moving. Using a multimeter to check the voltage and capacitor status can help diagnose the problem. It could also be due to poor switch contact or a loose power cord, so check if the plug is secure. When dealing with such issues, avoid disassembling the motor yourself to prevent electric shock risks. It's safer to consult a professional for inspection. Complex circuit problems require diagnostic tools.
