Fiat 1998 Marea Weekend, Service Manual

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Marea- Marea Weekend
©> Engine
99
range
Fuel system
10.
DIAGNOSTICS
The system is equipped with an autodiagnostic function which is designed to check for irregularities with
the following components:
Actuators Sensors
injectors engine speed sensor
coils vehicle speed sensor
charcoal filter soleniod valve Lambda sensor
engine idle adjustment actuator butterfly position sensor
electric fuel pump relay coolant temperature sensor
climate control relays (if fitted) detonation sensor
Location of diagnostic connector
4F015PJ01
The detection of a fault, if confirmed, involves
it being permanently memorized, in addition to
the exclusion of the sensor from the system
until it is restored.
The detection of a confirmed fault usually in-
volves: the warning light in the dashboard
coming on: the light goes out when the fault
conditions disappear.
NOTE During starting, the bulb:
- comes on for about 4 seconds;
- goes out for 0.1 secnods;
- remains on/off definitively according
to whether or not there are "perma-
nent" errors.
When working with the diagnostic equipment it is possible to carry out the complete fault diagnosis of the
system, which consists of three stages:
- display of a series of functional parameters (with the engine switched off or running);
- display of the errors and their cancellation;
- activation of some actuators (active diagnosis).
Recovery strategy
If a fault is detected with the sensors/actuators, the control unit, where possible, replaces the missing
data, reconstructing it using software (recovery) to allow the operation of the engine.
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