P0181 FTT Sensor: Description

The fuel tank temperature sensor is used to detect the fuel temperature inside the fuel tank. The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the fuel temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

< Reference data >

RESISTANCE REFERENCE CHART

Fluid temperature °C (°F)

Voltage⁽¹⁾ V

Resistance kΩ

20 (68)

3.5

2.3 - 2.7

50 (122)

2.2

0.79 - 0.90

⁽¹⁾	These data are reference values and are measured between ECM terminal 106 (Fuel tank temperature sensor) and ground.

Fig 1: Resistance And Temperature Graph

Courtesy of NISSAN NORTH AMERICA, INC.

CAUTION: Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.