Iveco Daily Euro 4. Manual — part 255
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ELECTRIC/ELECTRONIC SYSTEM
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The solenoid valve controls the lift of the atomiser needle.
On the fuel inlet union a filter protects the injector for
impurities. The injector is constructively the same as
conventional ones, except that there is no needle return
spring.
Access to the injectors is gained by releasing the side
soundproof cover from the cylinder head. The fuel recovery
pipe has a quick coupling.
The injector comprises two parts:
- actuator - atomiser composed of pressure rod (1), pin (2)
and nozzle (3)
- control solenoid valve comprising a coil (4) and drive
valve (5).
1
st
phase: rest position
The coil (4) is not activated and the shutter (6) is in the closed
position.
The same fuel pressure acts in both the control area (7) and
in the pressure chamber (8), but as the shutter (6) is closed,
the needle (2) cannot be raised.
2
nd
phase: start of injection
The coil (4) is energised and causes the shutter (6) to move
upwards.
The fuel of the control volume (9) flows towards the backflow
duct (10) causing a drop in the pressure in the control area
(7).
At the same time, the pressure of the fuel in the pressure
chamber (8) causes the needle (2) to rise, resulting in fuel
injection to the cylinder.
3
rd
phase: end of injection
The coil (4) is not activated and makes the shutter (6) return
to the closed position, which re-creates a balance of forces
that makes the needle (2) return to the closed position and
consequently end injection.
Injectors (78247)
The solenoid valve is of the N.C. type.
The injectors are connected individually to the control unit at
the following pins:
- A16 / A47 cylinder 1 injector
- A2
/ A31 cylinder 2 injector
- A1
/ A46 cylinder 3 injector
- A17 / A33 cylinder 4 injector
INJECTOR WIRING DIAGRAM AND CROSS SECTION
1. Pressure rod - 2. Needle - 3. Nozzle - 4. Coil - 5. Pilot
valve - 6. ball shutter - 7. control area - 8. pressure
chamber - 9. Control volume - 10. Backflow duct -
11. Control duct - 12. Supply duct - 13. Electrical
connection - 14. High pressure fuel inlet - 15. Spring
10
4
5
6
7
12
13
9
11
14
12
1
15
2
8
3
Figure 93
ELECTRIC/ELECTRONIC SYSTEM
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The fan is provided with an electromagnetic junction
monitored by the electronic centre pin A39 that activated
the junction remote control switch, to optimise water
cooling.
The electrical fan remote control switch is activated or
deactivated by the centre according to the temperature of:
- the coolant
- over supply air
- the fuel
Engine coolant temperature
Activated at over 96
°C and deactivated at under 84 °C
Over supply air temperature
Activated at over 75
°C and deactivated at under 65 °C
Fuel temperature
Activated at over 20
°C and deactivated at under 10 °C
ELECTROMAGNETIC JUNCTION TECHNICAL VIEW
1. Coil - 2. Connector
Figure 94
88064
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A semiconductor layer, immersed in a magnetic field and
through which current flows, generates a potential difference
(called Hall voltage) at its ends.
If current intensity remains constant, the generated voltage
depends only on the magnetic field strength: periodical
variation of field strength is enough to obtain a modulated
electric signal.
The smooth portion of the phonic wheel (distributing shaft
pulley) covers, while moving, the sensor, thus blocking the
magnetic field with resulting low output signal.
On the contrary, the sensor generates a high signal next to
the openings and when a magnetic field is available.
Phase sensor signals are acquired, and the engine position is
recognized according to the sequence of the phonic wheel
notches.
The mounting function makes it possible to identify signal
errors and interferences (if any).
The resulting signal is supplied to the processor that controls
the injection system.
It is connected to PINs A20, A50, A11 of central unit EDC16.
1. Phase identification holes
1. Distributing shaft pulley - 2. Sensor
PERSPECTIVE VIEW
1. Power supply positive - 2. Signal output - 3. Earth
1
3
2
Figure 95
Figure 96
0003320t
0003321t
Figure 97
85712
85713
ELECTRIC/ELECTRONIC SYSTEM
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The F1A engine crankshaft sensor features a slatted sound
wheel on the crankshaft front.
This features 58 (60-2) teeth and the sensor detects their
passage.
TECHNICAL VIEW OF THE SOUND WHEEL AND
SENSOR
1. Sound wheel — 2. Crankshaft sensor
Figure 98
Figure 99
0003319t
Characteristics of flywheel rpm and timing
system sensors
These are inductive sensors.
The flywheel sensor (48035) is connected at pins 27 and 12
of connector A of the control unit.
It is also used to control the electronic rev counter on the
instrument cluster.
The resistance at 20
°C is approx. ~ 860 Ohm.
SENSOR AND CONNECTION CABLE
SENSOR CONNECTOR AND WIRING DIRAGRAM
Figure 100
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