2429915 - 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
.
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 and sensor K47 , , 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.O. 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. 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
the signal coming from the clutch switch I31 (or, on versions with
a robotized gearbox, from the starting enablement switch on the
brake pedal I34).
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 - the signal for the minimum engine oil pressure
sensor
K30
.
The control unit M10 is connected
via the CAN network - pins 28, 60, 43, 11 - 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;
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 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.
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.