The seat heating circuit is controlled by relay R13 of under-dashboard junction unit B02.This is supplied directly by the battery via a line protected by fuse F2 contained in engine compartment control unit B01.The coil excitation signal consists of an earth signal leaving pin 14 of connector X of body computer M01.The power supply leaving relay R13 flows through fuse F45 and leaves under-dashboard junction unit B02 from pin 4 connector D.This sigal then reaches pin 2 of switch I65 contained in the driver''s side seat.When the switch is turned on, the power supply reaches heat pad O40, which heats the seat.The heat pad is earthed via pin 1.Operation of switch I65 also determines activation of the led in the switch.