The power supply to fans N11 and N12 reaches the battery directly via relays R6 and R7 contained in engine compartment junction unit B01 from a line entering pin 1 connector A of the control unit.The power supply to the relays is protected by fuses F7 for relay R7 and F6 for relay R6.These are excited by two different earth signals from engine control unit M10.Engine temperature sensor K36 measures the cdoolant temperature. If temperature values are high, control unit M10 sends an earth signal from pin 7 connector A to relay R6 (which controls the first fan speed), which excites the coil. Relay R6 then sends a power supply via resistance O10 to operate fan N11 at the first speed (slow).If the engine coolant reaches a higher temperature level, control unit M10 sends an earth signal from pin 8 of connector A to relay R7 which controls the second speed of fan N11, which thus turns at maximum speed.