What Causes the Car Air Conditioning Fan Not to Rotate and Fail to Cool?

[VonBentley]

There are several reasons why a car air conditioning fan does not rotate and fails to cool: Damaged expansion valve: The air conditioning compressor shows 'low pressure high, high pressure low, replace the compressor.' The probability of air conditioning compressor damage is not high; faults in the expansion valve and throttle valve directly lead to poor air conditioning cooling. Lack of refrigerant: Since the sealing device of the air conditioning system is not absolutely airtight, the refrigerant in general air conditioning systems tends to dissipate. Therefore, ordinary vehicles require refrigerant replenishment every 2-3 years. Some cars may even need it annually. If the car air conditioning system performs poorly in cooling, and after adding refrigerant for a period, it starts to cool poorly again, this indicates a condenser leak. The method to check for leaks is quite laborious. Generally, fluorescent dye is added to the refrigerant oil, and a special glass is used for inspection to locate the leak point.

[ORicardo]

I found that when the car's air conditioning fan doesn't spin and fails to cool, the most common issues are a faulty fan motor or electrical circuit problems. The fan is a critical component for heat dissipation; if it doesn't operate, the air conditioning system cannot effectively cool the refrigerant, resulting in poor cooling performance. Common causes include a seized fan motor bearing or burnt-out coils, which may result from prolonged high-temperature operation; a damaged relay that interrupts current flow; a blown fuse, typically found in the fuse box; or short circuits or open circuits in the wiring, cutting off power to the fan. During inspection, first listen for the fan's sound—if there's a humming noise but no movement, it's likely a motor issue; no sound indicates a broken circuit. Don’t overlook the possibility of the air conditioning pressure switch triggering a fault, as the system may automatically shut off the fan to protect components when pressure is too high. Ignoring the issue long-term may lead to compressor overload and damage, so timely testing at a repair shop is the best approach. Replacing a fuse yourself is simple, but a professional diagnosis is necessary for a thorough solution.

[DelLukas]

After driving for so many years, I've encountered several instances where the fan wouldn't spin and the AC wouldn't cool. Each time, the cause was simple yet annoying—like the fan being clogged with dust and debris, especially after the rainy season when leaves accumulate, or the motor burning out, which happens more often during the high temperatures of summer. The fan is the core of the cooling system; if it stops, the refrigerant can't cool down, and the AC just blows warm air. When checking, first turn on the AC to see if the fan spins. If it doesn't, check the fuse box—many times, I've fixed it just by replacing a fuse. If that doesn't work, the relay might be faulty; just get a friend to help test the voltage. Prolonged fan issues can affect engine cooling, increase fuel consumption, or even damage other components. Regular cleaning and maintenance of the AC system can prevent these problems, saving both money and hassle.

[VonFaith]

I think the reason why the car air conditioning fan not spinning may cause no cooling is due to a fan circuit failure. The fan is a key component for heat dissipation, and if it doesn't move, the air conditioning system cannot function effectively. Common issues include fan relay failure, blown fuse, or loose wiring causing power loss. The inspection steps are simple: after turning on the air conditioning, observe whether the fan starts. If it doesn't, check if the fuse is blown and use a multimeter to test for voltage. A non-spinning fan will prevent the condenser from dissipating heat, leading to cooling failure. Repair it as soon as possible to avoid compressor damage. It's recommended to seek professional diagnosis at a specialized shop, as internal issues like refrigerant leakage may also indirectly affect the system.