Review on 🌡️ Electric Engine Cooling Fan Thermostat Temperature Switch with 3/8" Pipe Thread - 185 to 175 Degree Temperature Sensor Switch, Compatible with 10" 12" 14" 16" Fans (with Pipe Thread) - Enhanced for SEO by Pedro Hague

. This part was used to turn the radiator fan on at 185 and off at 175. Make sure you have a relay that can source enough current to overcome the inrush current (at least twice the electric fan's rated current). This switch provides ground to the coil side of the relay and your key on the hot wire or ignition wire provides +12V. With this connection, the fan will turn on when the coolant temp reaches 185 degrees and run until the coolant temp drops below 175 degrees.