3363801 - E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT - Functional description
Functional description
The engine control unit
M10
monitors
and controls the entire electronic ignition and injection system.
The supply controlled by the ignition (15/54)
reaches pin 58 of
M10 from the line protected by fuse F16 of
the engine compartment unit B1.The main injection relay T9 of B1
controls the entire system: this is excited by a control signal
(earth) received from pin 31 of connector A of control unit M10
and then sends power:
- to pin 4 of the actual control unit, via the line from
fuse F17 of B1 ;
- to pin 5 of the actual control unit, via the line from
fuse F22 of B1 ;
- to the oil level sensor K31 , to the air flow meter K41 , to the solenoid valves L30 , L36 ; L62 ,
to the control unit M15 , via the line from fuse F11 of B1
The fuel pump relay T10 of
B1
is
supplied by the line of the fuse F21 of
B1
.
It is energized by a control signal (earth)
from pin 24 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.
Pins 1, 2 and 3 of
M10
are earthed.
The diesel pre-heating relay T19 of
B1
is
supplied by the line for fuse F20 of
B1
.
It is energized by a control signal (earth)
coming from pin 23 of the control unit
M10
and supplies
power to the diesel heating resistance
O20
.
Control unit
M15, which manages preheating
of spark plugs A40, is supplied directly from the battery via a
lline protected by fuse F4 of B1. It is supplied, connector C, by
the line for fuse F11 of B1 and exchanges command and control signals
with pins 22 and 62 of M10 which controls the timing.
Connector
B is connected to the heater plugs
A40.
The engine control unit
M10
receives
signals from the various sensors in order to monitor all engine
operating conditions.
The rpm sensor
K46
provides information
concerning the engine speed through a frequency 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 weak and are therefore
suitably shielded by pin 101.
Timing sensor
K47 is supplied from 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
K36
,
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
B1
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 turbocharger 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 for fuse F11 of
B1
and is controlled by a signal for pin 16 of
M10
.
The variable geometry solenoid valve
L36
regulates the operation of the turbine according to the engine load:
it is supplied by the line for fuse F11 of
B1
and is controlled by
a signal for pin 17 of
M10
.
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
B1
and is controlled by a signal for pin 15 of
M10
.
Pin 59 of
M10
receives the 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 59 of
M10
receives the 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 61 of
M10
receives an earth
signal coming from the clutch switch
I31
.
The injectors
N70
receive the opening
go ahead supply from pins 117 (cylinders 1 and 2) and 118 (cylinders
3 and 4) of
M10
.
The engine control unit sends commands to
the injectors
N70
from pins 119, 120, 121 and 114 of connector
A for cylinders 1, 2, 3 and 4, respectively.
The control unit
M10
receives the
minimum engine oil pressure sensor
K30
signal at pin 98.
The water in diesel filter sensor
K31
;
is supplied by the line for fuse F11 of
B1
and sends the
corresponding signal to pin 105 of
M10
.
The control unit M10 is connected
via the CAN network - pins 9, 10, 28 and 29 - to the Body Computer
M1 and the other nodes on the network: through this connection,
it sends information concerning:
- system self-test, which can be used by connecting to connector
C of M1.
- 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;
- water in diesel filter, which is sent to the instrument
panel E50 which manages the display.
It receives, via CAN, the speedometer signal
generated by the ABS control unit
M50
The self-test system of the control unit
M10
also generates a signal - which comes from pin 21 - which is connected
directly to the 'EOBD' warning light located in the instrument panel
E50.
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 48 from the control unit M10 via the specific tester line.