Fiat 1996 Brava Service Manual page 447

Bravo- Brava 9
1998 range
16v
Engine
Fuel system
INJECTION NTC
NTC
INSTRUMENT
c
-20
-10
0
10
20
25
30
Q
15970
9620
5975
3816
2500
2044
1679
C
40
50
60
70
80
90
100
Q
1150
807
576
418
309
231
176
60
90
120
Q
512-602
184-208
76-88
ENGINE
SENSOR
COOLANT
10.
TEMPERATURE
The sensor is fitted on the thermostat case;lt is
made up of brass casing which affords pro­
tection for the actual resistive elements con­
sisting of two NTC (Negative Temperature
Coefficient) type thermistors whose electrical
resistance decreases as the temperature in­
creases).
The two NTC thermistors are separate and
supply temperature inforfmation to a specific
indicator on the instrument panel and the in­
jection-ignition control unit
The reference voltage for the injection system
NTC element is 5 Volt: since the control unit
intake circuit is designed as a voltage divider,
the reference voltage is shared between a re­
sistance in the control unit and the actual sen­
sor. As a result, the control unit is capable of
evaluating the variations in the sensor resis­
tance through the changes in voltage, thereby
obtaining information concerning the tem­
perature.
1. NTC for injection system
2. NTC for indicator on instrument panel
Recovery
Assumes last temperature reading or a fixed
value of 80°C if intake air temperature ex­
ceeds a certain value.
Mixture concentration self-adaption is inhib­
ited.
The radiator fan is activated
Idle self-adapation is inhibited
Checking the resistance
The table alongside shows resistance values
that the NTC elements may assume as tem­
perature changes. These values can be meas­
ured by disconnecting the connector and
connecting an ohmmeter across the sensor
pins.
Removing-refitting
Disconnect the electrical connection and re­
move the sensor.
E
Tightening torque 2.2 d a N m
Connector wiring
The numbers in boxes indicate the respective
control unit pins.
Connection to coolant temperature gauge on instrument
panel