Abstract: The system includes a sensor operable to supply electrical signals indicating the temperature of the engine and further sensors operable to supply electrical signals indicating predetermined parameters established to define operating conditions of the motor vehicle. A processing and control unit is provided to select, on the basis of the signals supplied by the said further sensors, a corresponding predetermined function which correlates the electric power to be supplied to the fan assembly with the electric power to be supplied to the electric pump, in dependence on the heat energy extracted from the engine, in order to obtain the minimum sum of the said electric power values; and to determine, on the basis of the signals supplied by the first sensor and the said selected function, the values of electric power to be supplied to the electric fan and the electric pump.

Abstract: The system includes a hydraulic circuit for supplying a flow of coolant to the engine, comprising a circulation pump, a radiator connected to the engine, a by-pass duct parallel to the radiator, and a regulating valve capable of adjusting the ratio of the flows of liquid supplied to the engine through the by-pass duct and the radiator respectively. The output of the circulation pump varies as a function of a control signal. A sensor provides signals indicating the temperature of the liquid flowing through a predetermined zone of the engine or the hydraulic circuit. An electronic unit connected to the sensor controls the pump such that the output of this latter varies depending on the temperature detected by the sensor. The regulating valve modifies the ratio of the aforesaid flows of liquid as the output of the pump varies.