Repair Manual

17
IGNITION AND INJECTION
17 - 13
ENGINE TEMPERATURE SENSOR
The engine sensor T is an NTC type (negative temperature coefficient); its internal
resistance will decrease with the increasing of the temperature.
It is checked with an ohmmeter connected to the sensor terminals or even better with a
voltmeter, during the engine running The voltage of the cold engine should be U = 5 V;
this voltage decreases according to the heating of the engine. In case there is a short circuit
the voltage will drop, first slowly, then suddenly. This is a very precise diagnosis as it is
done under running.
The engine sensor T is not to be repaired but replaced.
Reference values: R sensor = 1450 - 3300 Ω la 15 - 30
0
C
R sensor = 2500 +/- 125 Ω la 20
0
C
The report between the sensor resistance and the temperature is:
T [
0
] - 10 0 10 20 40 60 80 100
R [ Ω ] 9200 5900 3700 2500 1180 600 325 190
DESCRIPTION OF THE SYSTEM
vnx.su