Description
(1) engine ECU
"a" 64-way grey connector
"b" 48-way grey connector
Role
The engine ECU manages the fuel injection on the basis of the information on engine torque
- The engine ECU calculates the need for engine torque from data from the accelerator pedal sensor
- The engine torque request takes account of a number of corrections (torque absorbed by the alternator, torque absorbed by the aircon compressor,...)
- The engine torque request converts into a fuel injection time, a fuel injection phasing, a command to open the throttle unit and an ignition advance
The engine ECU manages the ignition as well as the injection of the fuel, as a function of the different parameters received
- Engine speed
- Position of the crankshaft
- Inlet air pressure (atmospheric pressure sensor)
- Position of the accelerator pedal
- Engine temperature (coolant thermistor)
- Temperature of the air entering the cylinders (air temperature sensor)
- Engine coolant temperature
- Torque absorbed by the alternator
- Torque absorbed by the aircon compressor (calculation)
- Vehicle speed (vehicle speed sensor; speed information provided by the ESP ECU)
- Oxygen content in the exhaust gases (upstream oxygen sensor)
- Engine knock (knock detector)
- Air conditioning request (*)
- Voltage of the service battery
- Pressure in the power steering circuit
NoteThe atmospheric pressure sensor is incorporated in the engine management ECU and cannot be separated from it
Using this information, the engine ECU operates the following commands
- Opening of the motorised throttle unit
- Adjustment of idling speed
- Ignition advance and coil charging time
- Quantity of petrol injected, proportional to the injectors opening time
- Petrol vapours recirculation (canister bleed electrovalve)
- Cutting of the injection in overload and deceleration
- Air conditioning cut-off
- Oxygen sensor heating resistor (upstream oxygen sensor, downstream oxygen sensor)
The engine ECU controls also the following functions
- Reduction of engine torque during an activation of the ESP (*)
- The engine cooling
- The cooling requirement for the air conditioning (BRAC)
- The dialogue with the ECUs on the CAN network (Controller Area Network)
- Check functionalities of injection and pollution control
- Driving improvement strategies
- Engine immobiliser function
- Emergency strategies
- Fan unit and warning lamp operating management
- The diagnostic with memorisation of failures
- The cruise control and speed limiter function (*)
Note(*) according to specification
Electrical features
| channel number | allocation of channels of connector |
|---|---|
| 1 | control: oil supply valve |
| 2 | control: injector N° 1 |
| 3 | control: injector N° 2 |
| 4 | control: ignition coil for cylinder N°1 |
| 5 | control: ignition coil for cylinder N°2 |
| 6 | control of the starter relay |
| 7 | channel not connected |
| 8 | information from the engine speed sensor |
| 9 | supply of 5 V applied to the cylinder reference sensor and to the engine speed sensor |
| 10 | motorised buttery housing main position sensor information |
| 11 | motorised throttle housing secondary position sensor information |
| 12 | 5 V supply applied to the motorised throttle housing position sensor |
| 13 | motorised throttle housing position sensor earth |
| 14 | information from the cylinder reference sensor |
| 15 | motorised throttle housing valve servo control positive control |
| 16 | motorised throttle housing valve servo control negative control |
| 17 | channel not connected |
| 18 | control: injector N° 3 |
| 19 | control: injector N° 4 |
| 20 | control: ignition coil for cylinder N°3 |
| 21 | control: ignition coil for cylinder N°4 |
| 22 | channel not connected |
| 23 | channel not connected |
| 24 | Earth of the engine speed sensor |
| 25 | detonation sensor information |
| 26 | coolant temperature sensor information |
| 27 | coolant temperature sensor earth |
| 28 | channel not connected |
| 29 | channel not connected |
| 30 | earth of the cylinder reference sensor |
| 31 | channel not connected |
| 32 | channel not connected |
| 33 | channel not connected |
| 34 | Heating control of downstream Lambda sensor |
| 35 | Heating control of upstream Lambda sensor |
| 36 | engine oil pressure switch information |
| 37 | Purge canister solenoid valve control |
| 38 | Downstream oxygen sensor signal |
| 39 | downstream oxygen sensor earth |
| 40 | Upstream oxygen sensor signal |
| 41 | upstream oxygen sensor earth |
| 42 | detonation sensor earth |
| 43 | channel not connected |
| 44 | supply of 5 V applied to the manifold absolute pressure sensor |
| 45 | air inlet manifold absolute pressure sensor information |
| 46 | air inlet manifold absolute pressure sensor earth |
| 47 | channel not connected |
| 48 | channel not connected |
| 49 | channel not connected |
| 50 | channel not connected |
| 51 | channel not connected |
| 52 | channel not connected |
| 53 | channel not connected |
| 54 | channel not connected |
| 55 | channel not connected |
| 56 | channel not connected |
| 57 | channel not connected |
| 58 | channel not connected |
| 59 | channel not connected |
| 60 | control of the piloted alternator |
| 61 | piloted alternator control copy |
| 62 | piloted alternator output voltage signal |
| 63 | channel not connected |
| 64 | channel not connected |
| channel number | allocation of channels of connector |
|---|---|
| 1 | body earth |
| 2 | supply via the throttle servo control relay |
| 3 | engine control relay control |
| 4 | accelerator pedal position main sensor information |
| 5 | 5 V supply applied to the accelerator pedal position main sensor |
| 6 | accelerator pedal position main sensor earth |
| 7 | accelerator pedal position secondary sensor information |
| 8 | 5 V supply applied to the accelerator pedal position secondary sensor |
| 9 | accelerator pedal position secondary sensor earth |
| 10 | diagnostic socket |
| 11 | body earth |
| 12 | supply via engine control relay |
| 13 | body earth |
| 14 | motorised throttle housing servo control relay control |
| 15 | diode |
| 16 | channel not connected |
| 17 | channel not connected |
| 18 | channel not connected |
| 19 | air inlet temperature sensor information |
| 20 | CAN-C High |
| 21 | CAN-C Low |
| 22 (*) | position via ignition switch ignition switch position via starting button |
| 23 | body earth |
| 24 | channel not connected |
| 25 | ignition switch information |
| 26 | fuel pump relay control |
| 27 | channel not connected |
| 28 (*) | ancillaries battery temperature sensor information |
| 29 | 5 V supply applied to the ancillaries battery current sensor (*) |
| 30 (*) | ancillaries battery current sensor information |
| 31 (*) | ancillaries battery current sensor earth |
| 32 | control of the air conditioning compressor relay |
| 33 | diagnostic socket |
| 34 | service battery positive |
| 35 (*) | position via ignition switch |
| 36 | starter relay control |
| 37 | ignition switch relay control |
| 38 | brake lamp switch relay control |
| 39 | channel not connected |
| 40 | channel not connected |
| 41 | channel not connected |
| 42 | channel not connected |
| 43 | channel not connected |
| 44 | channel not connected |
| 45 | channel not connected |
| 46 | channel not connected |
| 47 | channel not connected |
| 48 | channel not connected |
Programming - initialisation
The engine management ECU software is updated by downloading (ECU fitted with a flash EPROM)