For some reason, every time I turn on the ventilation system for the cabin, the radiator fan goes on and off constantly and in one instance I got a warning on the iDrive screen that the engine is overheating. It went away after a few minutes of turning the engine off and it drives fine, but we keep hearing the radiator fan go on and off very loudly.
My car has 50000 miles.
My car has an automatic transmission.
Hello - for virtually all modern cars, setting the heater/AC controls on any position that utilizes the air conditioning compressor (i.e. defrost), the auxiliary fan for the radiator is automatically turned on to increase airflow over the AC condenser coil (in front of the radiator). Your BMW does the same. The "overheat" warning, however, is not normal, and should be checked out - even if it is only a bad sensor. I would recommend a cooling system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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