Why does the car air conditioning cooling fan keep running at high speed?
2 Answers
When the temperature is too high, it operates at high speed, and when the temperature is normal, it operates at low speed for cooling, which is a normal phenomenon. Related introductions are as follows: 1. Classification: According to the direction of coolant flow in the radiator, radiators can be divided into two types: longitudinal flow and cross flow. According to the structure of the radiator core, radiators can be divided into tube-fin radiator cores, tube-belt radiator cores, and plate-type radiator cores. 2. Material: There are mainly two types of car radiators: aluminum and copper. The former is used for general passenger cars, while the latter is used for large commercial vehicles. The materials and manufacturing technology of car radiators are developing rapidly. While aluminum radiators are gradually replacing copper radiators in the field of cars and light vehicles due to their obvious advantages in material lightweighting, the manufacturing technology and process of copper radiators have made significant progress. Copper brazed radiators have obvious advantages in engine radiators for buses, construction machinery, and heavy trucks.
In my car repair experience, a common issue is the high-speed rotation of the air conditioning fan. This is usually caused by a stuck or short-circuited fan control relay. The relay is responsible for adjusting the fan speed, and once the internal contacts stick together, the fan will continue to run at high speed. A faulty temperature sensor can also mislead the system, causing the fan to always run at high speed. During inspection, start the engine and turn on the air conditioning, then use a multimeter to test the relay terminals to see if they are stuck in the closed position. If replacing the relay doesn’t work, check whether the sensor signal is normal. It could also be due to excessive pressure in the air conditioning system, forcing the fan to run at high speed to cool and protect the components. In this case, check the refrigerant level and the cleanliness of the condenser. A fan running continuously at high speed increases the burden on the battery and reduces its lifespan, so professional repair is recommended in a timely manner. During regular maintenance, pay attention to cleaning the engine compartment to avoid moisture or aging and short circuits in the circuit components, which can prevent similar faults.
