Fiat 1998 Marea Weekend, Service Manual

Page: 299 / 846

Marea- Marea Weekend ft
99 update
16v
Engine
Fuel system
INJECTION NTC
INSTRUMENT
NTC
°c
Q,
°C Q
-20 15971 40
1152
-10 9620 50 807
0 5975 60 576
10 3816 70 418
20 2502 80 309
25 2044 90 231
30 1679 100 176
°C Q
60
90
120
512-602
184-208
76-88
KS1
B
T H 2 0
10.
ENGINE COOLANT TEMPERATURE S E N -
SOR
This sensor is fitted on the thermostat.
It consists of a brass casing which affords
protection for the resistive elements, compris-
ing two NTC type thermistors (Negative Tem-
perature Coefficient, where the electrical resis-
tance decreases as the temperature increases).
The two thermistors are distinctive and provide
information for the instrument panel (A) and
the engine management control unit (B), re-
spectively.
The reference voltage for the latter is 5 Volt:
since the control unit input circuit is designed
as a voltage divider, the reference voltage is
shared between a resistance in the control unit
and the actual sensor.
As a result, the control unit is capable of
evaluating the variations in the sensor resis-
tance through the changes in the voltage,
thereby obtaining information concerning the
temperature.
The table illustrates the sensor progress, which
can be measured by disconnecting the con-
nector and connecting an ohmmeter as shown
in the diagram.
Wiring connector
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