Page 86 of 330

Marea- Marea Weekend 9 \) JTD
2000 range O
Engine
Index
FUEL SYSTEM
- Introduction
- System management strategies
- Fuel system functional diagram
- Diagram showing information ente
ring/leaving the control unit and
sensors/actuators
INJECTION SYSTEM WIRING DIA
GRAM
- Injection electronic control unit
- Rpm sensor
- Timing sensor
- Air flow meter
- Injectors
- Engine coolant temperature sensor
- Fuel temperature sensor
- Fuel pressure sensor
- Heater plugs control unit
- Accelerator pedal potentiometer
- Brake pedal switch
- Clutch pedal switch
- Excess pressure sensor
- Atmospheric pressure sensor
page
1
1
1
2
8
10
12
13
13
14
15
15
15
16
16
17
17
17
17
THROTTLE CASING
- Removing-refitting
E.G.R. VALVE
- Removing-refitting
E.G.R. VALVE SELF-ADJUSTMENT
MOTOR
- Removing-refitting
E.G.R. VALVE HEAT EXCHANGER
- Removing-refitting
SOLENOID VALVE ON VACUUM
RESERVOIR FOR THROTTLE CA
SING PNEUMATIC VALVE
- Removing-refitting
VACUUM RESERVOIR
- Removing-refitting
10.
page
30
31
32
32
34
34
FUEL SUPPLY CIRCUIT 18
- Immersed (auxiliary) pump and fuel
gauge assembly 19
- Fuel filter 19
- Pressure pump 20
- Fuel pressure regulator 20
- Multifunction valve 21
- Supply manifold (rail) 21
- Inertia safety switch 22
AIR SUPPLY CIRCUIT 23
- Throttle case 24
- Turbocharger 25
SUPERCHARGING PRESSURE
CONTROL SOLENOID VALVE
- Removing-refitting 35
FUEL FILTER
- Removing-refitting 35
PRESSURE REGULATOR
- Removing-refitting 36
EMISSION CONTROL DEVICES 27
- Oxidizing catalytic converter 27
- Exhaust gas recirculation circuit
(EGR) 27
- Recirculation circuit for crankcase
vapours (blow-by) 29
Copyright by Fiat Auto VI 01 Cancels anil replaces
Page 94 of 330
Engine
Fuel feed system
Marea- Marea Weekend 9 ™
2000 range O
10.
INJECTION SYSTEM WIRING DIAGRAM
4F008XJ01
8 Publication no. 506.763/24
Page 95 of 330

Marea- Marea Weekend 9 ™
2000 range ©) Fuel feed system
Engine
10.
Compents of injection system wiring diagram
1. Vehicle speepd
2. Rev counter
3. Engine radiator fan low speed relay
4. Radiator fan high speed activation relay
5. Potentiometer on accelerator pedal
6. Timing sensor
7. Fuel pressure sensor
8. EGR system modulator solenoid
9. Fuel pressure regulator
10. Glow plug preheating warning light on control panel
11. Injection system failure warning light
12. Air conditioning system relay
13. Coolant temperature sensor
14. Rpm sensor
15. Fuel temperature sensor
16. Diagnostic socket
17. Fiat CODE control unit
18. Four stage pressure switch
19. Injection electronic control unit
20. Pressure relief sensor
21. 7.5A fuse protecting electronic injection system ( + 15 power supply from ignition switch)
22. 7.5A fuse protecting electronic injection system ( + 30 power supply from ignition switch)
23. Main injection system relay
24. 30A fuse protecting injection system
25. Auxiliary fuel pump relay
26. Glow plug preheating control unit
27. Intake air flow and temperature sensor (debimeter)
28. Brake pedal switch
29. Clutch pedal switch
30. Ignition switch
31. Battery
32. Inertia switch
33. Auxiliary fuel pump (submerged in tank)
34. 60A fuse protecting glow plug control unit
35. Cylinder no. 1 glow plug
36. Cylinder no. 2 glow plug
37. Cylinder no. 3 glow plug
38. Cylinder no. 4 glow plug
39. Cylinder no. 1 injector
40. Cylinder no. 2 injector
41. Cylinder no. 3 injector
42. Cylinder no. 4 injector
43. Throttle valve control solenoid
44. Variable geometry turbocharger control solenoid
45. Diesel filter heater relay
Copyright by Fiat Auto 9
Page 96 of 330

Engine Marea- Marea Weekend 9 ™
Fuel feed system 2000 range @
10.
ELECTRONIC INJECTION CONTROL UNIT
The control unit processes signals from the various sensors by applying software algorithms and controls
the actuators accordingly (particularly the injectors and pressure regulator) to achieve the best possible
engine service conditions.
The control unit is "flash E.P.R.O.M." type, i.e. it can be reprogrammed from outside without andy need
to adjust the hardware.
The injection control unit contains a built-in absolute pressure sensor and is connected to the wiring by
means of a 121 pin connector.
Control unit connection identification (PIN-out)
4 5 43 24 6 25 96 106 113 105 119 120 121
1 Earth 25 Not connected
2 Earth 26 Not connected
3 Earth 27 Not connected
4 Actuator power supply 28 Not connected
5 Injector/ECU power supply 29 Not connected
6 Not connected 30 Not connected
7 Not connected 31 Not connected
8 Not connected 32 Not connected
9 Not connected 33 Not connected
10 Not connected 34 Not connected
11 Fiat CODE 35 Not connected
12 Not connected 36 Not connected
13 Injection relay
14 Glow plug control
15 Throttle body solenoid
16 EGR valve
17S VGT solenoid
18 Air conditioner relay
19 Radiator fan high speed relay
20 Radiator fan low speed relay
21 Diagnostic warning light control
22 Glow plug activation control
23 Not connected
24 Auxiliary fuel pump relay
10 Publication no. 506.763/24
Page 122 of 330
Engine
Fuel feed system
Marea- Marea Weekend @ ™
2000 range ©
PRESSURE REGULATOR
NOTE During the operations of removing-
refitting the pressure regulator, work
in extremely clean conditions.
Removing
- If the vehicle is equipped with a shield un
der the engine, remove it.
1. Remove the engine oil filler plug (1), then
undo the fixing nuts (2) and remove the
sound insulation cover (3).
2. Undo the bolts (1) fixing the retaining
bands for the injector wiring.
Disconnect the electrical connectors (2) for
the injectors and place the wiring to the
side.
- Release the injection cable loom from the
retaining bands.
3. Undo the nuts (1) fixing the fuel return
manifold pipe (2) to the intake manifold.
Place the fuel return manifold pipe to the
side.
4. Disconnect the electrical connector (1) for
the pressure regulator, then undo the bolts
(2) fixing the regulator to the pump.
36 Print n° 506.763/25
Page 131 of 330

Marea- Marea Weekend
2000 range ©
Electrical equipment
Protection and security devices
55.
PROTECTION AND SAFETY DEVICES
All the vehicle supply lines were designed taking into account the most up-to-date directives in terms of
safety and protection, especially to prevent fires.
There are 2 types of protection:
- active protection, aims to reduce the causes of faults "at source"
- passive protection, aims to limit the effects of a fault as much as possible
The first category includes a carefully designed wiring layout with wires positioned and carefully anchored
on tracks that are repaired and protected if necessary.
The cables connected to the alternator and the motor were modified for this reason by adding protective
caps etc. A strengthened sheath was also introduced for some of the more exposed sections of wiring.
The passive protection includes all interventions to reduce faults due to high current (overload, short cir
cuit).
All system fuses were rated based on the nominal absorbtion of the loads activated at the same time, to
ensure intervention in cases of a clear short circuit.
The introduction of a box containing 4 maxifuses with other fuses connected on the outside means all
the supplies can be protected except for the cable that connects the battery to the starter motor and the
cable that connects the starter motor to the recharging alternator. These cables are therefore protected by a
strengthened supplementary sheath.
In "MAXI" fusebox A:
EFI electronic injection fuse (petrol)
GLOW: plug fuse (diesel)
IGN: ignition switch fuse
J/B2 fuse master supply .
J/B1 fuse master supply
Next to the box.
B: fan fuse (see table)
C: ABS 60A fuse
D: second fan fuse: 40A (JTD)
115961 1998
iFil 30A IJ/B21 BOA
fiGNl 4OA IJTBTI BOA
1910JTD
IGLOWl 60A P7B21 80A
MGNI 40A IJ/Bll 80A
FUSE B
30A engine petrol without air conditioner
40A 1596 with air conditioning, JTD
50A 1998 wth air conditioning
Copyright by Fiat Auto 1
Page 132 of 330
Electrical equipment
Protection and safety devices
Marea- Marea Weekend
2000 range ©)
55.
Main supplies wiring diagram (petrol engine types)
Component key
3B/C Power fusebox
3A/D Supplementary fusebox
4 Junction unit
10 Engine battery earth
10A Bodyshell battery earth.
11 Battery
12 Ignition switch
96 Power fuse protecting A.B.S
129 Engine cooling fan protection power fuse.
332 Ignition activated power relay.
(*) See table on previous page.
2 Print n° 506.763/23
Page 133 of 330
Marea- Marea Weekend
2000 range ©)
Electrical equipment
Protection and safety devices
55.
Main supplies wiring diagram (diesel engine types)
Component key
3B/C Power fusebox
3A/D Supplementary fusebox
4 Junction unit
10 Engine battery earth
10A Bodyshell battery earth
11 Battery
12 Ignition switch
96 Power fuse protecting A.B.S
129 Engine cooling fan protection power fuse.
129A Power fuse protecting engine cooling fan
no.2
201 Heaer plugs control unit
332 Ignition activated power relay.
Copyright by Fiat Auto 3