Q: When I turn ON the Heater The Radiator Fan turns ON too and make the car engine cold could you please tell me the solution the fan

Hi there. Is the climate control set to defrost on the windshield? If so, this still engages the ac compressor and turns the radiator fans on. What is the current coolant level? A slow coolant leak may leave a trail of dried coolant, but the level may not be enough to cause overheating at the moment. If the coolant level is low this will affect the operating temperature of the engine and heater as well. A low coolant level can affect your air condition when the weather warms up; having a coolant concern corrected before summer can avoid possible air conditioner concerns. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a heater does not work inspection.