What are the reasons for the BMW 325 fan not spinning?
2 Answers
BMW 325 fan not spinning reasons introduction: Coolant temperature not reaching standard: Most modern car radiator fans operate with electronic temperature control, so the fan usually only starts spinning normally when the engine coolant reaches the required temperature. If the temperature is too low, the radiator fan won't spin. Therefore, when the car radiator fan fails to spin, the first thing to check is whether the coolant temperature meets the requirement. Relay malfunction: If the relay malfunctions, the car's radiator fan won't work either. Thermostat switch problem: If there are no issues with the above two aspects, then you should check the thermostat switch. Sometimes faults can occur here, which can also affect the operation of the car radiator fan, so this should also be checked.
I've run an auto repair shop for ten years, and the BMW 325's fan not spinning usually has three common issues. First, electrical circuit problems—maybe a blown fuse, a failed fan relay, or poor wire contact preventing current flow. Second, issues with the fan motor itself—severely worn carbon brushes, seized bearings stopping the blades, or internal coil breakage. Third, temperature control malfunctions—the coolant temperature sensor falsely reporting low temps, so the ECU doesn't send a start signal, or the control module's program glitches and sends erratic commands. When washing the car, avoid blasting water directly at the radiator—moisture seeping into the motor connector often causes copper contacts to rust, a problem I've seen many times.
