223002902 - E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT - FUNCTIONAL DESCRIPTION

Functional description

The engine control unit M10 monitors and controls the LUCAS EPIC electronic injection system. The control unit receives a supply controlled by the ignition (15/54) at pin 81 from the line protected by fuse F21 and controlled by relay R10 . The signal which controls the coil for the relay R10 coming out of pin 11 connector F of the engine compartment junction unit B01 is earthed through a bridge between pins 3 and 4 of the electric fuel pump N40 and the inertia switch I50 . In the case of an impact it interrupts the supply for the control unit M10 .The relay R9 controls the system supply: it receives a supply from the battery at pin 1 of connector A of the engine compartment junction unit B01 ; the coil is supplied by the same line and is energized by an earth signal coming from the control unit M10 , from pin 82. This energizing makes it possible to supply pins 76 and 77 of the control unit M10 via fuse F17 of the engine compartment junction unit B01 .

The engine control unit M10 receives signals from the various sensors in order to monitor all engine service conditions.

  • The sensor K46 provides information concerning the engine speed through an alternating signal sent to pin 11 of the control unit M10 . It receives an earth signal from pin 74 of the control unit. Both signals are suitably screened (pin 80);
  • the engine temperature sensor K45 , receives a reference earth from pin 66 of the control unit M10 and supplies a signal proportional to the temperature of the engine coolant to pin 34;
  • the insufficient engine oil pressure sensor K30 sends an earth signal, if activated, to pin 18 of the engine control unit;

Other components (actuators), controlled by the control unit M10, allow the correct operation of the engine.

  • The butterfly valve solenoid valve L62 is supplied by the relay R9 from the line for fuse F11 of the engine compartment junction unit B01 . It receives an earth from the engine management control unit M10 (from pin 65) and, in turn, sends information concerning the air temperature via pin 4, whilst pins 29 and 48 are used for the correct operation of the throttle.
  • The EGR solenoid L30 controls exhaust gas recirculation. It is supplied by the relay R9 , from the line protected by fuse F11 and from pin 39 of the engine control unit. The solenoid valve then exchanges certain information with the control unit via pins 35, 59 and 63.
  • The control unit M15 , which manages the pre-heating of the heater plugs A40 , is supplied (connector B pin 1) directly by the battery via the line protected by fuse B37 and via the line (connector A pin 3) for fuse F11 of the engine compartment junction unit B01 . It receives commands from pin 52 of M10 which controls the timing and sends a feedback signal to pin 49 of the control unit. Connector B is connected to the heater plugs A40. Pins 78 and 79 of M10 , together with pins 1 and 2 of connector A of M15 , are earthed.
The injection control unit M10 exchanges information with the body computer M01 concerning the correct operation of the system via the CAN line, from pins 1 and 2 of the control unit to pins 36 and 37 of connector C of the body computer. The diagnostic line from pin 33 of the control unit to pin 20 of the body computer also travels between the two systems. A fault in the injection system is highlighted by the warning light in the instrument panel E50 , the management of irregularities is therefore controlled by the body computer logic. The body computer is also responsible, always using the same lines, for lighting up the heater plugs warning light when the ignition is switched ON.The body computer M01 also receives values from the speedometer sensor K84 at pins 15 and 17 of connector C.

The EPIC N41 injection pump is equipped with numerous internal sensors which send information to the engine management control unit M10. These connections should be suitably screened:

  • cam sensor, pin 13;
  • cam sensor resistance, pin 12;
  • rotor sensor, pin 14;
  • cam sensor/rotor supply, pin 15;
  • diesel temperature signal, pin 36.
The control unit is therefore capable of imposing the correct control actions for the pump N41 from pins 30, 51, 60, 67, 89 and 90.