184002245 - E5030 PETROL ENGINE ELECTRONIC MANAGEMENT - FUNCTIONAL DESCRIPTION

Functional description

The engine control unit M10 monitors and controls the entire electronic ignition and injection system.The control unit M10 is supplied directly by the battery at pin 18 of connector A, via the line protected by fuse F18 of engine bay control unit B1 .The supply controlled by the ignition (15/54) reaches pin 51 of connector A of M10 from the line protected by fuse F16 of the engine compartment unit B1 .Connector C of M10 is earthed.

The main injection relay T9 of B1 controls the entire system: this is excited by a control signal (earth) received from pin 19 of connector A of control unit M10 and then sends power:

• to the injectors N70 and the coils A30 , via the line protected by fuse F22 of B1 .
• to the fuel vapour recovery solenoid L10 and the Lambda sensors K15 and K17 via a line protected by fuse F11 of B1
• to pins 17, 33 and 49 of control unit M10, via the line protected by fuse F17 of B1;

The fuel pump relay T10 of B1 is supplied from the line of fuse F21 of B1.It is energized by a control signal (earth) from pin 62 of connector A of control unit M10 and supplies power to fuel pump N40 , which is earthed through the inertia switch I50 , which cuts off the circuit in the case of a crash and so prevents the dangerous spilling of fuel.The engine control unit M10 receives signals from the various sensors in order to monitor all engine service conditions.Rpm sensor K46 provides information on engine speed via a frequency signal sent to pins 10 and 42 of connector B of control unit M10 . These two signals are very low intensity and are therefore shielded.Timing sensor K47 is supplied from pin 7 of connector B of control unit M10. It receives a reference earth from pin 9 of connector B and sends a frequency signal corresponding to the timing to pin 36 of M10 .The integrated air temperature sensor K43 receives a reference earth from pin 26 of connector B; it sends a signal corresponding to the intake air temperature to pin 55 of the control unit. From pin 7 of M10 a reference supply is sent to the sensor K43 which restores a signal, to pin 6, proportional to the pressure of the intake air.Engine temperature sender unit K36 receives a reference earth from pin 9 of connector B of control unit M10 and supplies a signal proportional to coolant temperature to pin 38 of the same connector.The detonation sensor K50 provides information concerning the onset of detonation in the combustion chamber through frequency signals: it sends two signals to pins 21 and 37 of connector B of M10 ; these signals are also suitably shielded.The Lambda sensor at the pre-catalyzer K15 and the one at the catalyzer K17 provide the control unit M10 with information concerning the correct composition of the air/fuel mixture:The sensor K15 sends a signal to pin 8 of connector B of the control unit, whilst pin 25 provides a reference earth: the intensity of these two signals is extremely low and therefore they are appropriately shielded. Sensor K15 is heated by a resistor in order to ensure it works efficiently even when cold; the resistance is supplied by the main relay T9 ; pin 49 of connector B of M10 provides the reference earth.The sensor K17 sends a signal to pin 57 of connector B of the control unit, whlst pin 41 provides the reference earth:the intensity of these two signals is extremely low and therefore they are appropriately shielded. Probe K17 is heated by a resistor in order to ensure it works efficiently even when cold; the resistance is supplied by the main relay T9 ; pin 17 of connector B of M10 provides the reference earth.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 21 and 22 respectively of connector A of M10 and sends a corresponding signal to pin 54 of the same connector. The second receives power and earth from pins 5 and 4 respectively of connector A of M10 and sends a corresponding signal to pin 37 of connector A.Pin 25 of connector A of M10 receives an N.A. positive signal coming from the brake lights switch I30, with the supply controlled by the ignition (INT) from fuse F37 of the junction unit B2.Pin 57 of connector A of M10 receives an N.C. positive signal coming from the brake lights switch I30, with the supply controlled by the ignition (INT) from fuse F35 of the junction unit B2.Pin 7 of connector A of M10 receives a negative signal coming from the clutch switch I31.The control unit M10 controls the opening of the injectors N70 via special signals sent from pins 51, 18, 2 and 34 of connector B of M10 . The injectors N70 receive a power supply to enable the opening from the main relay T9 of B1 .The control unit M10 also controls the coil A30 through the signals for the coil primary winding, whilst the secondary winding sends a pulse to the spark plugs: from pins 32, 16, 31, 15 of connector B of M10 . The coil A30 primary windings receive a signal to enable opening from the main relay T9 of B1 .Throttle body actuator N75 is fitted with two built-in potentiometers connected in parallel: they control throttle opening via a stepper motor.The motor receives power from pins 11-43 and 28-60 of connector B of M10 . Pin 56 of connector B sends a power supply to both potentiometers, pin 58 supplies an earth signal to the potentiometers, while pins 39 and 23 of the same connector receive signals from the throttle body actuator N75 .Fuel vapour recovery solenoid L10 allows fuel vapours to pass through to the engine intake where they join the mixture entering the combustion chamber. Valve L10 is supplied by the main relay T9 of B1 ; it is opened by the control unit when the engine is loaded by a signal from pin 33 of connector B of M10 .The control unit M10 receives - at pin 42 of connector A - a negative signal for the minimum engine oil pressure sensor K30.The engine coolant temperature control unit M10 which is sent to the instrument panel E50 which manages the gauge and the engine rpm warning light, which is sent to the rev counter from the instrument panel E50; miinimum engine oil pressure, which is sent to the instrument panel E50 which manages the warning light;It receives, via CAN, the speedometer signal generated by the ABS control unit M50The self-test system of the control unit M10 also generates a negative signal - which comes from pin 31 of connector A - which is connected directly to the ''EOBD'' warning light located in the instrument panel E50.The check function inside the instrument panel E50 also controls the intervention of the inertia switch, any faults in the engine temperature sensor and the oil pressure sensor: if faults are detected, the ''fault'' warning light is switched on and, at the same time, the information is shown on the display.The self-test data can be read by connecting to connector C of the Body Computer M1 - pin 7: it receives the signals from pin 2 of connector A from the control unit M10 via the specific tester line.