Activation of the engine cooling fans integral with radiator prewiring N011 is managed by signals from engine control unit M010:- fan activation level 1 - pin 8 of N011 -, from pin 90 of connector A of M010;- fan activation level 2 - pin 5 of N011 -, from pin 69 of connector A of M010;- fan activation level 3 - pin 1 of N011 -, from pin 94 of connector A of M010;Radiator unit N011 receives a power supply (direct from the battery) via fuses located in engine compartment control unit B001: from fuse F6 for the fan low speed relay (pin 3 of N011) and from fuse F7 for the fan high speed relay (pin 7 of N011) respectively.Pins 2 (low speed fan) and 6 (high speed fan) are connected to earth C045.Engine coolant sensor K036 receives a reference earth and sends a temperature signal to engine control unit M010, to pins 41 and 58 of connector B respectively.Linear sensor K120 receives a power supply and reference earth from pins 22 and 12 of connector A of M010 respectively and sends a pressure signal to pin 13 of connector A of M010.