Radiator Cooling Fan: Description and Operation
SYSTEM OUTLINEIf the ignition SW is turned to ON, the current from the FR IG fuse is sent to the coil side and the FAN relay is turned to ON.
Then the current flows to TERMINAL 3 of the cooling fan ECU. At the same time, the conditions of the A/C SW, A/C pressure sensor, engine coolant temp. sensor and engine rotation are sent to the TERMINAL 2 as signals from the TERMINAL RFC of the engine control module. As a result of that, the cooling fan ECU continuously controls the rotation of the fan motor and keeps a balance between the cooling efficiency and silentness with the optimal fan rotation.