Fiat 1998 Marea Weekend, Service Manual

Page: 197 / 846

Marea-Marea Weekend^
1998 range
16v
Engine
Fuel system
10.
Communication between control unit and tester
A socket in the engine bay is used for connection of a tester device.
Information is exchanged between control unit and tester by means of a two-way tester line (K line) and
the communicaiton protocol is to Key Word 2000 standards. Data are transmitted in NRZ positive logic
at a rate of 10400 Bauds.
The tester can provide the following information:
- Engine parameter display;
- Error display;
- Active diagnosis.
Displayed parameters
Engine rpm
Injection time
Absolute pressure to inlet manifold
Inlet air temperature
Coolant temperature
Butterfly valve opening angle
Battery voltage
Number of engine idle speed actuator open/¬
close steps
Advance
Mixture correction (Lambda probe)
Vehicle speed
Self-adaptability
Error counter
Ignition coil load time (Dwell)
Petrol vapour solenoid
Start-up counter
Engine load
Fiat CODE
List of errors
RPM sensor
Throttle potentiometer
Absolute pressure sensor
Air temperature sensor
Coolant temperature sensor
Battery
Lambda probe
Injectors
Ignition coils
Idle speed actuator
Fuel vapour solenoid
Actuator relays
Control unit
Signal absent
A.C.-D.C.
A.C.-D.C.
A.C.-D.C.
A.C.-D.C.
Power supply > 16.2V
Power supply < 6V
Implausible signal
D.C.
A.C.-D.C.
A.C.-D.C.
A.C.-D.C.
A.C.-D.C.
A.C.-D.C.
Microprocessor or ECU memory faults are indi-
cated.
Self-adaptive parameters
Speed sensor
Knock sensor
Fiat CODE
Indication displayed when ECU self-adaptive
limits reached.
This indicates that engine parameters are too
far removed from specified values. It is therefore
advisable to look for mechanical and other
faults.
Implausible signal
Speed greater than top speed
A.C.-D.C.
Code not recognised or not received
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