What are the reasons for the car's AC fan not turning on?
2 Answers
The reasons why the car's AC fan does not turn on are as follows: 1. Poor contact of the main control switch: When the main control switch has poor contact, with resistance too high or zero, it should be repaired or replaced. 2. Damage to the fan motor coil: When the fan motor coil is damaged, with resistance too high or zero, it should be repaired or replaced. 3. Loose fastening screw between the fan motor and the blade: If the fastening screw between the fan motor and the blade is loose, it needs to be tightened. 4. Open or short circuit of the fan capacitor: If the fan capacitor is open or short-circuited, replace it with a capacitor of the same specification. The working principle of the car air conditioning system is that the car air conditioning refrigeration system consists of a compressor, condenser, liquid storage dryer, expansion valve, evaporator, and blower, among others. These components are connected by copper pipes and high-pressure rubber hoses to form a sealed system. When the refrigeration system operates, the refrigerant circulates in different states within this sealed system.
My car had a similar issue before—when I turned on the AC, the fan didn’t make a sound at all. After some troubleshooting, I found a few common causes. First, it might be a blown fan fuse, as the circuit protection cuts off when the current is too high. Second, a faulty fan relay is quite common—it controls the fan startup and can fail over time. Or, the fan motor itself might be burnt out, which is the most straightforward possibility, especially if dust buildup from long-term use causes overheating. Also, check the AC control panel switch—poor contact or a short circuit can prevent signals from reaching the fan. Loose wiring connections can cause this too, like a loose plug or damaged wires. In my case, it was a fuse issue—just a small cost to replace it. If left unfixed, driving in summer with no AC can be unbearable, affecting comfort and distracting the driver. I’d suggest checking the fuse location in the engine bay box first; if that doesn’t work, take it to a professional shop for inspection.
