How to Determine if a Car Fan is Functioning Normally?
2 Answers
Determine whether the car fan is functioning normally based on the following conditions: 1. Based on water temperature: When the water temperature reaches 100 degrees, which is when the air conditioning is turned on, the fan operates at low speed; when the water temperature reaches 112 degrees, the fan operates at high speed. 2. Based on air conditioning pressure: Connect the high and low pressure gauge hoses to the system's high and low pressure service (charging) ports respectively. Set the air conditioning system to the coldest setting, the blower speed to the highest, set to internal circulation, and the air outlet mode to face direction with all doors open. Then run the air conditioning system (the engine should maintain a certain speed, usually 1500r/min; using idle speed alone will affect the accuracy of fault diagnosis). Observe the pressure gauge group (for R12 or R-134a, normal working pressure is: low pressure side at 1.8～2.1kgf/cm2, high pressure side at 12～14kgf/cm2 and 13～15kgf/cm2 respectively). If the pressure is not within this range, the air conditioning system has a fault.
I remember in the past when driving, I would always check if the fan was working properly before each maintenance. The method was quite simple: after a cold start, let the engine warm up to operating temperature, about ten minutes, then observe or listen to see if the fan automatically starts. If the fan begins to rotate when the engine is hot, with smooth and noiseless operation and sufficient speed, it indicates normal functioning. Another point is to inspect the integrity of the fan blades, ensuring there are no cracks or deformations that could affect balance. I also made it a habit to regularly clean dust off the radiator to prevent the fan from overworking. If the fan suddenly stops, the temperature gauge will spike, which is a warning signal. It's best to have a technician test the circuit relays and fuses annually to ensure there are no aging issues. Maintaining the fan properly can prevent engine overheating and protect the vehicle, extending its lifespan.
