ROBOTIZED GEARBOX - Functional description

1.2 8v · Smart gearbox

Functional description

The Selespeed gearbox control unit M054:

• at pin 27 connector A receives the direct battery supply from the line protected by fuse F32;
• at pin 28 connector A receives the ignition-controlled supply, from the line protected by fuse F16;
• at pin 1, 2, is connected to earth C011.

During the engine starting stage, the control unit M054 sends a negative signal from pin 42 connector A to the coil for relay T20, housed in the engine compartment junction unit B001. The relay, when energized, closes its internal contact, supplying the starter motor A020 (for more details see See E5010 STARTING AND RECHARING ). At pin 76 connector B the Selespeed control unit receives the engine starting signal (+50) supplied by the ignition switch H001.

Starting is only permitted if the Selespeed control unit:

• at pin 74 connector B receives the 'lever in neutral' signal provided by the gear controls unit H037;
• at pin 69 connector B receives the brake pedal pressed signal, supplied by the N.A. circuit coming from the brake pedal switch I030 (see wiring diagram See E7023 ESP ).

If the vehicle is stationary, with a gear engaged, if the Selespeed control unit receives the driver's door open signal at pin 78 connector B, the system automatically engages neutral.

The Selespeed control unit receives gear increase signals (pin 26 connector A) and gear decrease signals (pin 68 connector B) via the gear controls unit H037. The gears control unit receives an ignition-controlled supply at pin 6 and an earth reference at pin 1 (the earth reference is supplied by the Selespeed control unit from pin 65 connector B).

The shift to AUTO mode takes place via the robotized gearbox AUTO function swithc H034. The signal (referred to earth C011) is sent to pin 77 connector B of control unit M054. The latter, depending on the engine rpm supplied by the engine management control unit M010 (pin 63 connector B) at pin 48 connector A makes provision for the gears at the automatic transmission.

From pin 31 connector A, the Selespeed gearbox control unit M054 controls the engagement of the Selespeed gearbox oil pump N047, whose supply is controlled by a specific relay located inside the engine compartment junction unit B001.

Control unit M054:

• from pins 32, 44 connector A controls the gear engagement solenoid valves L051 and L052;
• from pin 29 connector A it controls the gear selection solenoid valve L053;
• from pin 43 connector A it controls the clutch control solenoid valve L056;
• from pins 79, 59 connector B it provides the supply and earth reference, respectively, for the clutch position potentiometer K095 which sends its own signal to pin 52 connector A of the control unit;
• from pins 73, 66 connector B it provides the supply and earth reference, respectively, for the pressure sensor on the gearbox K096, the gear engagement potentiometer K069 and the gear selection potentiometer K068;
• at pin 40 connector A receives the signal from the pressure sensor on the gearbox K096;
• at pin 39 connector A receives the signal from the gear engagement potentiometer K069;
• at pin 51 connector A receives the signal from the gear selector K068;
• at pin 38 it provides the supply for the gearbox output speed sensor K077;
• at pin 50 it receives the signal from the gearbox output speed sensor K077.

The buzzer in the instrument panel E050 is activated, from pin 80 connector B, by control unit M054 if there are problems or faulty operation caused by the driver.

System problems are indicated by the warning light in the instrument panel coming on; the signal is sent via the C CAN to the body computer node M001 which controls the instrument panel E050 via the B CAN (for more details See E4010 INSTRUMENT PANEL ).

The Selespeed control unit M054 also has an autodiagnostic function sending its own data from pin 49 connector A to the diagnostic coupling R010 (for more details see See E8010 DIAGNOSTIC MULTIPLE CONNECTOR ).

The Selespeed control unit communicates via the C CAN from pins 7, 19, 33, 45 connector A (see wiring diagram See E1050 CAN CONNECTION LINES ).