G420F(FE) Service Manual Chapter 5. Engine Management System (EMS) 199
LP Fuel Temperature Sensor
Location
Description
The LP Fuel Temperature Sensor (FTS) is located in
the LP fuel passage of the LP mixer for detecting the
LP fuel temperature. The FTS uses a thermistor
whose resistance changes with the temperature.
The electrical resistance of the FTS decrease as the
temperature increase, and increase as the
temperature decrease. The reference 5V in the ECM
is supplied to the FTS by way of a resister in the
ECM. That is, the resistor in the ECM and the
thermistor in the FTS are connected in series. When
the resistance value of the thermistor in the FTS
changes according to the LP fuel temperature, the
output voltage also change.
[Circuit Diagram]
[Harness Connectors]
Inspection
1. Remove the LP fuel temperature sensor from the
adapter connected to LP mixer.
2. With the temperature sensing portion of the LP
engine fuel temperature immersed in hot water,
check resistance.
Temperature °C (°F) FTS Resistance (Ohms)
-20(-4) 15462
0(32) 5896
20(68) 2498
40(104) 1175
60(140) 596
80(176) 323
3. If the resistance deviates from the standard value
greatly, replace the sensor.