223002915 - E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT - FUNCTIONAL DESCRIPTION
Functional description
Engine control unit M10 monitors and controls the electronic injection system. The supply for the engine control unit M10 is controlled by the ignition (15/54) at pin 58 by the line protected by fuse F16 of the engine compartment junction unit B01 .The main injection relay R9 housed in junction unit B01 controls the entire system: it is energized by a control signal (earth) received from pin 13 of control unit M10 and then sends power:
- to pin 4 of the actual control unit, via the line from fuse F17 of B01 ;
- to pin 5 of the actual control unit, via the line from fuse F22 of B01 ;
- to the water in the diesel filter sensor K31 , to the air flow meter K41, to the solenoid valves L30 , L35 and L62 , t the control unit M15 , via the line from fuse F11 of B01 .
The engine control unit M10 receives signals from the various sensors in order to monitor all engine service conditions.
- The rpm sensor K46 provides information concerning the engine speed through an alternating signal sent to pin 100 of the control unit M10 . It receives an earth signal from pin 99 of the control unit. Both signals are suitably screened (pin 101);
- Timing sensor K47 is supplied by pin 102 of M10 . It receives a reference earth from pin 104 of the control unit M10 and sends it a signal of frequency corresponding to the timing of pin 103.
- The engine temperature sensor K45 , receives a reference earth from pin 85 of the control unit M10 and supplies a signal proportional to the temperature of the engine coolant to pin 84.
- The air flow meter K41 receives a general supply from the line for fuse 11 of B01 and a reference voltage from pin 88 of M10 . It is supplied by the control unit from pin 97 of M10 and sends a signal proportional to the air flow rate to pin 89. K41 also contains an air temperature sensor which sends an air temperature signal to pin 86 of M10 .
- Accelerator pedal K55 is fitted with two built-in potentiometers (a main one and a safety back-up). The first receives power and earth from pins 78 and 76 respectively of M10 and sends a corresponding signal to pin 77. The second receives power and earth from pins 81 and 79 respectively of M10 and sends the signal to pin 80.
- The fuel temperature sensor K81 measures the temperature of the diesel entering. It receives a reference earth from pin 83 of M10 and sends the fuel temperature signal to pin 82.
- The supercharging sensor K82 measures the engine supply pressure. It is supplied by pin 93 of M10 and receives a reference earth from pin 95. The signal is sent to in 94 of the control unit.
- The fuel pressure sensor K83 is responsible for providing the injection control unit with a feedback signal for governing injection pressure and duration. It receives the power and reference earth from pin 90 and 92, respectively of M10 ; it then sends the pressure signal to pin 91.
- The fuel pressure regulator N77 has the task of keeping the value of the fuel pressure in the accumulator constant. The two control signals come from pins 108 and 109 of the control unit M10 .
- The EGR solenoid L30 controls exhaust gas recirculation. It is supplied by the line protected by fuse F11 and from pin 16 of the engine control unit M10 . The solenoid valve then exchanges certain information with the control unit via pins 35, 59 and 63.
- The solenoid valve on the throttle casing L62 shutters and closes the throttle, for example when the engine is switched off; it is supplied by the line for fuse F11 of B01 and is controlled by a signal for pin 15 of M10 .
The control unit M10 is connected via the CAN - pins 6, 7 and 48 - to the Body Computer M01 and the other nodes in the network: through this connection, it sends information concerning:
- system self-test, which can be displayed by connecting the diagnostic equipment to connector C of M01 .
- engine water temperature, which is sent to the instrument panel E50 which manages the relevant gauge and warning light;
- rpm, which is sent to the rev counter of the instrument panel E50 ;
- engine oil minimum pressure, which is sent to instrument panel E50 which manages the relevant warning light;
- heater plugs pre-heating, which is sent to the instrument panel E50 which manages the appropriate warning light.