841005989 - E7050 AUTOMATIC TRANSMISSION OPERATIONAL DESCRIPTION

Operational Description

The automatic transmission control unit M055 controls and regulates the entire gearbox management system.The direct supply (+30) for the control unit arrives, via the line protected by fuse F64 of the luggage compartment junction unit B045, at pin 7 of connector B.The supplies controlled by the ignition (INT) reach pin 10 of connector A through the line protected by fuse F37 of the junction unit under the dashboard B002 and pins 18 and 19 of connector B as for the automatic transmission gear selector control unit M053 (pin 1) via the line protected by fuse F51 of junction unit B002.The automatic transmission control unit does not allow the vehicle to be started up if a gear is engaged through the ignition switch solenoid L057 conected to the actual control unit at pin 1 of connector A.The automatic transmission solenoid unit L050 receives a supply at pin 10 of connector A through the line protected by fuse F23 and via relay R20, both located in the engine compartment junction unit B001.The automatic transmission gear selector control unit 053 warns the automatic transmission control unit M055 (pins 3 and 4 of connector A) that a gear is engaged via the C-CAN from pins 5 and 7.The instrument panel E050, supplied by the line controlled by the ignition (INT) protected by fuse F37 of the junction unit under the dashboard B002 (pin 1 of connector A) and the line from the battery (pin 2 of connector A) protected by fuse F53 inside junction unit B002, receives the signal for the gear engaged, via the B-CAN (pins 3 and 4 of connector A) displaying it on the appropriate milometer.The speedometer signal, supplied by the braking system control unit M051 (pin 16), reaches pin 7 of connector A of the Body Computer M001, which transmits it, via the B-CAN, to the other control units involved in the function.The automatic transmission control unit M055 receives the automatic transmission fluid overheating signal from the solenoid valve unit L050 (pins 3 and 6 of connector C) at pins 21 and 22 of connector B and transmits it, via the C-CAN, from pins 12 and 13 of connector A in the same way as it transmits a possible fault for the automatic transmission to be shown as a message on the instrument panel E050 display.The (normally open) brake pedal switch I030 provides the automatic transmission control unit (pin 10 of connector A) with the status of its contacts from pin 2.The automatic transmission control unit manages its own diagnostic signal from pin 11 of connector A.    See E8010 DIAGNOSTIC MULTIPLE CONNECTORThe automatic transmission control unit M055 activates the Ice function automaticlaly, in other words it allows safer driving when there is ice on the surface of the road; this function is activated through the signal that arrives via the B-CAN from the outside temperature sensor. The Body Computer M001 transmits the driver''s front door open signal, to the automatic transmission control unit M055, via the C-CAN, for the acoustic warning and the management of reverse gear and the automatic transmission safety position to the instrument panel E050.