The control unit of robotised transmission M54 controls and governs the entire gearbox management system. The power supply from the battery reaches the battery from the line of fuse F23 of engine compartment control unit B1, at pin 27 of connector A of M54. The ignition-operated power supply (15/54) reaches pin 28 of connector A of M54, via the line of fuse F16 of control unit B1.1, pins 1 and 2 of connector A of M54 are earthed.A group of sensors and potentiometers on the gearbox inform the control unit of the gear engaged: the potentiometers are receive a power supply from pin 73 of connector B; pin 66 provides the reference earth: Gear selection potentiometer K68 returns a signal to pin 51 of connector A. The gear engagement potentiometer K69 returns a signal to pin39 of connector A. Hydraulic unit oil pressure sensor K96 returns a signal to pin 40 of connector A. Clutch position sensor K95 is supplied from pin 79 of connector B. It receives a reference earth from pin 59, returns a signal to pin 52 of connector A of M54. Pins 38 and 50 of connector A M54 are connected to the speed sensor (gearbox outlet) K77.Gear control unit H37 is connected to control unit M54 to indicate the gear engagement request: these signals are sent to pins 67, 74, 68 of connector B of M54 and to pin 26 of connector A; from pin 66 of conector B it receives a reference earth while a power supply is received from the ignition operated line (15/54) protected by fuse F16 of engine compartment control unit B1.The operating mode selection button E H34 is connected to control unit M54 at pin 77 of connector B. This button is supplied from the line (INT) protected by fuse F51 of underfacia control unit B2. Pin 69 of connector B of M54 receives a signal from the brake light switch I30 with an ignition-operated supply (INT) from fuse F37 of underfacia control unit B2.On the basis of the operating logic the control unit controls the electro-hydraulic unit located in the gearbox which produces the gear changes: via pin 31 of connector A, a command reaches pump N47, which maintains the fluid in the hydraulic unit under pressure. Pump N47 is controlled by a special relay J87 supplied by the line of shunt fuse B43. The control unit also controls the opening of the hydraulic unit solenoids. Pins 32 and 44 of connector A of M54 send a control to both gear engagement solenoids L51 and L52. Pin 29 of M54 controls the gear selection solenoid L53. Pin 43 3 of connector A of M54 controls the control solenoid of clutch L56. Pin 42 of connector A of M54 issues a safety signal for the ignition enablement relay. pin 50 of starter motor A20; pin 76 of connector B receives an ignition request signalControl unit M54 also manages the doors open signal: the driver''s front door opening signal - lock N50 - reaches pin 78 of connector B of M54. Via the CAN network - pins 33-45 and 7-19 of connector A of M54 - signals are sent for the gearbox failure in instrument panel E50 and for the gear indication display in the instrument. The speedometer signal is also acquired via the CAN network. Pin 48 of connector A is connected to engine management control unit M10 from which it receives an engine rpm signal. Pin 80 of connector B issues a command to the buzzer, also located inside instrument panel E50.The autodiagnostic data can be read by connecting to connector G of the Body Computer M1 - pin 7l: it receives the signals from pin 49 of connector A of M54. (the line is shared with engine control unit (M10) via the tester line..