2000 FIAT MAREA start engine

Fuel feed system
Engine Marea- Marea Weekend 9 ™
2000 range (Q)
10.
Control of idle speed
On the basis of signals from the rpm sensor and engine coolant temperature sensor, the injection control
unit controls the pressure governor and alters the injector control times to maintain idle speed stable at all
times.
Under certain conditions, the idle speed control unit also considers battery voltage.
Control of maximum speed limitation
According to rpm level, the injection control unit limits maximum speed by means of two types of inter­
vention:
- as maximum speed approaches, it reduces the amount of fuel injected to reduce line pressure;
- when maximum speed is exceeded, it inhibits operation of the auxiliary pump and injectors.
Control of maximum torque limitation
On the basis of rpm level, the injection control unit computes limit torque and maximum permitted fume
index parameters on the basis of predefined, stored maps.
It then corrects the above parameters using engine coolant temperature and car speed data. The resulting
values are then used to modulate the amount of fuel to be injected by adjusting the pressure regulator and
injectors.
Control of fuel temperature
The injection control uint is kept constantly informed of fuel temperature by a sensor on the return mani­
fold.
If fuel temperature exceeds a set value (about 110 °C), the control unit reduces line pressure by adjusting
the pressure governor, leaving injection times unaltered.
Control of coolant temperature
The injection control unit is constantly informed of coolant temperature by a sensor on the thermostat.
If engine coolant temperature or air conditioning fluid pressure exceeds certain levels, the control unit
performs the following actions:
- It reduces the amount of fuel injected by adjusting the pressure governor and injectors (power reduc­
tion);
- it controls the engine radiator cooling fan.
Control of glow plugs
The injection control unit controls operation of the glow plug preheating control unit to bring the tem­
perature in the combution chambers up to levels that promote fuel self-ignition and thus make start-up
easier.
The control unit controls the operation of the glow plug control unit for a certain time both before (pre­
heating) and after (postheating) engine start-up and also controls activation of the warning light on the
control panel.
Preheating, postheating and glow plug warning light activation times vary according to engine coolant
temperature.
4 Publication no. 506.763/24

Fuel feed system
Engine Marea- Marea Weekend © ™
2000 range @
10.
The control unit autodiagnostic system checks the signals coming from the sensors and compares them
with the figures allowed:
- signalling faults during starting
- warning light on for 4 seconds indicates test stage
- warning light off after 4 seconds indicates no fault with components that could alter the pollution con­
trol standard figures
- warning light on after 4 seconds indicates fault.
- signalling faults during operation
- warning light on indicates fault
- warning light off indicates no fault with components that could alter the pollution control standard fig­
ures.
- recovery
- from time to time, the control unit defines the type of recovery according to the components which are
faulty
- the recovery parameters are managed by components which are not faulty.
Control of cylinder balancing during idling
According to the signals coming from the sensors, the injection control unit controls the idle speed torque,
altering the injector operating times.
Control of irregular operation
Depending on the signals coming from the sensors, the injection control unit corrects the amount of fuel
to be injected in order to improve driveability and reduce jerking whilst driving.
The correction is achieved through the fuel pressure regulator and by varying the injector operating times.
Control of electrical balance
According to the battery voltage, the injection control unit alters the idle speed, to guarantee a sufficient
current supply from the alternator in situations where the consumers are absorbing a great deal of power.
The variation in the idle speed is achived by regulating the fuel pressure and altering the injector operat­
ing times.
VGT variable geometry turbocharger control (1910 JTD 110 CV)
The injection control unit processes the signal coming from the supercharging sensor, at the various en­
gine operating speeds, and determines the quantity of fuel to be injected, acting on the fuel pressure
regulator and the injector opening times.
In addition, through the solenoid valve, the control unit regulates the geometry of the turbine in order to
ensure optimum performance in all operating conditions.
Turbocharger waste gate valve control (1910 JTD 100 CV)
At the various engine operating speeds, the injection control unit processes the signal coming from the
supercharging sensor and determines the amount of fuel to inject, acting on the fuel pressure regulator
and the injector opening times.
In addition, the control unit controls the opening of the turbocharger waste gate valve, via the solenoid
valve, in order to ensure excellent performance in all operating conditions.
Control of throttle closing when engine is switched off
When the engine is switched off (ignition key in OFF position) the injection control unit closes the throt­
tle valve located on the air intake duct via the special solenoid valve.
This action makes it possible to limit the tiresome shuddering of the engine whilst it is switching off.
6 .i. V!-01-.Cancelftand replaces Print n° 506.763/25

Engine
Fuel feed system
10.
1. Pressure rod
2. Pin
3. Nozzle
4. Coil
5. Pilot valve
6. Ball plunger
7. Control area
8. Supply volume
9. Control volume
10. Fuel outlet connector (low pressure)
11. Control port
12. Supply port
13. Electrical connection
14. Fuel input connector (high pressure)
15. Spring
Marea- Marea Weekend 9 ™
2000 range (Q)
INJECTORS
The injectors are fitted to the cylinder head
and are electromagnetic in type. They are
controlled directly by the injection control
unit.
The injectors come with a high-pressure sup­
ply port and a recirculation pipe at environ­
mental pressure; The supply port is connected
to a delivery manifold (rail) with pipes de­
signed to withstand the high service pressures.
The injector can be divided into two parts:
- Actuator/spray made up of a pressure rod
(1), pin (2) and nozzle (3);
- control solenoid made up of coil (4) and
pilot valve (5).
Operation
Injector operation may be divided into three
stages:
1. rest position
Coil (4) is deactivated and plunger (6) is in
closed position to prevent fuel entering the
cylinder: Fc > Fa where Fc is the force gener­
ated by pressure acting on the control area (7)
of pressure rod (1) and Fa is the force due to
the pressure acting on supply volume (8).
2. Start of injection
Coil (4) is excited and causes plunger (6) to
rise. Fuel flows from control volume (9) to
the return manfold to bring about a pressure
drop in control area (7). Simultanteously, line
pressure through supply port (12) exerceses a
force Fa > Fc on supply volume (8) to cause
pin (2) to rise and thus allow fuel into the
cylinders.
3. end of injection
Coil (4) is deactivated and causes plunger (6)
to return to closed position. The resulting bal­
ance of forces makes pin (2) return to rest po­
sition and injection therefore ends.
14 Publication no. 506.763/24

Auxiliary Units
Climate control
Marea-Marea Weekend
2000 range O
50
COMPRESSOR (1910 JTD)
The compressor fitted on this version is the SANDEN SD7V16 variable capacity type.
The capacity of the compressor varies starting from the maximum value (161.3 cm^/rev) and is gradually
reduced (up to 10.4 cm^/rev) according to the system load variations. - changed outside temperature
and/or humidity conditions or sharp variations in the engine load.
This solution is defined as "unlimited variable capacity".
The compressor is the alternating piston type: the variation in capacity is achieved by tilting the connect­
ing rod holder plate with a consequent variation of the piston stroke: the movement of the plate is acti­
vated by an internal regulation valve according to the balance of pressure upstream and downstream of
the compressor. In particular, a low intake pressure involves the shuttering of the compressor (reduced ca­
pacity), whilst a high pressure involves operation at maximum power (maximum capacity).
7 6 4 3 2
5 9
1 Diaphgram valve
2 Pistons
3 Connecting rods
4 Connecting rod plate
5 Shaft
6 Pin
7 Arm
8 Slide
9 Guide
Pa Intake pressure
Pi Pressure inside the compressor
Pm Supply pressure
Operation
The SD7V16 compressor is illustrated in the diagram; it consists of seven pistons (2) and connecting rods
(3) fastened to a connecting rod holder plate (4). The rotary motion of the plate (4), on the shaft (5)
produces the alternating movement of the pistons.
A change in the plate angle allows an alteration in capacity: maximum inclination (as in the diagram) for
maximum capacity; almost zero inclination (vertical position) for minimum capacity (virtually nil).
The plate (4) rotates around the pin (6) hinged on the shaft (5) arm (7).
The movement of the plate (4) in relation to the shaft (5) takes place by means of splining made from a
low resistance material.
The plate (4) slides below along a guide (9) via a runner (8) made from a low friction material.
The diaphragm valve (1) controls the flow rate adjustment according to the difference between Pa (intake
pressure) and Pi (pressure inside the compressor).
N.B. the solution adopted for this compressor is designed to keep the internal pressure Pi constant, with
advantages in terms of ease of adjustment and quiet, smooth operation.
2 Print n° 506.763/23

Marea-Marea Weekend
2000 range ©)
Auxiliary Units
Climate control
50
COMPRESSOR ( 1998 engine)
The compressor fitted on this version is the SANDEN SD6V12 variable capacity type.
The capacity of the compressor varies starting from the maximum value (125.1 cnrfVrev) and is gradually
reduced (up to 6.2 cm /rev) according to the system load variations. - changed outside temperature
and/or humidity conditions or sharp variations in the engine load.
This solution is defined as "unlimited variable capacity".
The compressor is the alternating piston type: the variation in capacity is achieved by tilting the connect­
ing rod holder plate with a consequent variation of the piston stroke: the movement of the plate is acti­
vated by an internal regulation valve according to the balance of pressure upstream and downstream of
the compressor. In particular a low intake pressure involves the shuttering of the compressor (reduced ca­
pacity), whilst a high pressure involves operation at maximum power (maximum capacity).
1. Diaphgram valve
2. Pistons
3. Connecting rods
4. Connecting rod plate
5. Shaft
6. Pin
7. Arm
8. Slide
9. Guide
Operation
The operation is the same as described for the previous SANDEN 7V16 compressor.
Copyright by Fiat Auto 3

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

Marea-Marea Weekend Electrical equipment
2000 range (§) Location of components on the car
55.
LOCATION OF RELAYS AND FUSES ON THE VEHICLE (BONNET - Petrol engine types)
Fi998l152B 273 274 i * *
3B-3C Power fusebox
96 Power fuse protecting ABS
98 Headlamp washer intermittent function
122 Engine cooling fan low speed relay
123 Engine cooling fan high speed timer
124 Air condiitoning compressor control relay
129 Power fuse protecting engine coling fan
150 Injection system relay feed
151 Lambda probe control relay for fuel pump
and injectors
152 Fuse protecting injection system
152A Fuse protecting injection system
152B Fuse protecting injection system
273 Fuse protecting automatic transmission
system
274 Fuse protecting automatic transmission
system
276 Starter enablement relay
(••) Versions with air conditioning
(*) With automatic transmission
Copyright by Fiat Auto 9

Marea-Marea Weekend Electrical equipment
2000 range (§) Wiring diagrams
55.
DESCRIPTION
Engine types
DESCRIPTION 10i 0) c.a. 01/70
ANTI-LOCKING BRAKING SYSTEM (ABS) AND FAILURE WARNING LIGHT 67 67 67 67
STARTING - ELECTRONIC IGNITION AND INJECTION - RECHARGING AND WARNING LIGHT - INSUFFICIENT ENGINE OIL PRESSURE WARNING LIGHT - INJECTION SYSTEM FAILURE WARNING LIGHT -
REV COUNTER 69 69 — 71
STARTING - ELECTRONIC INJECTION - RECHARGING AND WARNING LIGHT - LOW ENGINE OIL PRESSURE WARNING LIGHT - HEATER PLUGS WARNING LIGHT - INJECTION SYSTEM FAILURE WARNING
LIGHT - FUEL PREHEATING — — 73 —
STARTING - EGR CONTROL - INJECTION CONTROL - HEATER PLUGS AND WARNING LIGHT - RECHARGING AND WARNING LIGHT - LOW ENGINE OIL PRESSURE WARNING LIGHT — — — —
AUTOMATIC TRANSMISSION - SYSTEM FAILURE WARNING LIGHT — 75 — —
DIAGNOSTIC SOCKECT CONNECTIONS 77 77 77 77
PREPARATION FOR TAXI 79 79 79 79
FM.B. The numbers in the table correspond to the page number of the electrical system in the manual
Copyright by Fiat Auto III