223002814 - E5030 PETROL ENGINE ELECTRONIC MANAGEMENT - FUNCTIONAL DESCRIPTION

Functional description

The engine management control unit M10 monitors and controls the entire electronic ignition and injection system.It is supplied directly by the battery at pin 4 of connector B via the line protected by fuse F18 , housed in the engine compartment junction unit B1 .The supply controlled by the ignition (15/54) reaches pin 17 of connector B from the line protected by fuse F16 also housed in the engine compartment junction unit B01 , whilst pin 1 of connector C is earthed.

The control unit M10 energizes the relay R9, via a control signal coming out of pin 6 of connector B, which delivers the supply via two different lines protected by fuses F11 and F22 to the:

  • injectors N70 ;
  • ignition coil A30 ;
  • vapour recovery solenoid valve L10 ;
  • speedometer sensor K84 ;
  • Lambda sensors K30 and K40 ;
  • electric fuel pump N40 ;
The relay R9 is supplied directly from the battery at pin 1 of connector A of B01 , while the coil receives an ignition-operated supply (15/54) from the line protected by fuse F16;The electric fuel pump N40 is earthed through the inertia switch I50 which, in the case of an impact, cuts off the circuit and stops the supply of fuel.The idle actuator N74 regulates the by-pass line. It is controlled by the control unit M10 through the signals from pins 9 and 19, 17 and 18 of connector A. The fuel vapour recovery solenoid L10 allows fuel vapours to pass through to the engine intake where they join the mixture entering the combustion chamber. The valve L10 , supplied by the main relay R9 , is opened by the control unit when the engine is loaded by a signal from pin 26 of connector A of M10 .The injectors N70 are controlled by the control unit as well as the relay R9 also through special signals sent from pins 28, 36, 37 and 27 to the actual injectors.The control unit M10 also controls the coil A30 through the signals for the coil primary winding, whilst the secondary winding sends the impulse to the spark plugs (from pin 38 of the control unit for the pair of cylinders 1 & 4 and from pin 10 for cylinders 2 & 3).

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

  • The rpm sensor K46 sends information, through an alternating frequency sent to pins 25 (positive) and 35 (negative) of the control unit M10 via the screened line (pin 34), concerning the engine speed;
  • The timing sensor K47 provides information on the engine timing to the control unit through a signal sent to pins 24 and 32 (negative) of the control unit M10 via the screened line (pin 34);
  • The air temperature and pressure sensor K43 receives a signal corresponding to the temperature from pin 14 of connector A of the engine control unit M10 at pins 13 and 22 concerning the supply and the signal which concerns the pressure; these signals are screened appropriately;
  • The throttle position sensor K56 is supplied at 5 V from pin 32 of connector A of M10 and receives a reference earth from pin 20 connector A; it sends, through a potentiometer, a signal proportional to the degree of opening of the butterfly to pin 3 of connector A of M10 ;
  • the engine temperature sensor K45 , receives a reference earth from pin 29 of the control unit M10 and supplies a signal proportional to the temperature of the engine coolant to pin 5 of the control unit;
  • the detonation sensor K50 provides information concerning the onset of detonation in the combustion chamber through alternating signals: it sends two signals to pins 6 (positive) and 15 (negative ) of connector A of M10 ; these signals are also suitably screened (pin 8 connector A);
  • the heated Lambda sensor K40 provides the control unit M10 with information concerning the correct composition of the air/fuel mixture: the signal is exchangd with pin 22 (positive) and pin 32 (negative) of connector B of the control uni both suitably screened (pin 34). The sensor K40 is heated by a resistance to ensure that it works properly even when cold; the resistance is supplied by the main relay R9 through the line protected by fuse F11 ; the control unit sends an earth signal from pin 11 of connector B;
  • the 2nd Lambda sensor K39 through pin 1 and the screened lint to pins 21 and 31 of the control unit M10 ;
  • Pin 23 of connector A of the engine control unit receives the signal for the insufficient engine oil pressure switch K30 .
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 20 and 29 of connector B of the control unit to pins 37 and 36 of connector C of the body computer. The diagnostic line from pin 16 of the control unit to pin 10 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 M01 also receives values from the speedometer sensor K84 at pins 15 and 17 of connector C.The control unit M10 is connected to the air conditioning system via pins 12, 27, 28 and 38. This makes it possible to adjust the engine idle speed as the load increases each time the compressor is switched on or to switch off the compressor in the case of high engine speed or load conditions (    See E6021 COMPRESSOR ENGAGEMENT).The control unit also controls the engine cooling system: pins 8 and 18 control the engagement of the relevant fan (    See E5020 ENGINE COOLING).