DTC P0127: IAT Sensor: Description

The intake air temperature sensor is built-into mass air flow sensor (1). The sensor detects intake air temperature and transmits a signal to the ECM.

The temperature sensing unit uses a thermistor which is sensitive to the change in temperature. Electrical resistance of the thermistor decreases in response to the temperature rise.

NOTE: ECM uses only the intake air temperature sensor (bank 1) for engine control and self-diagnosis. It does not use the intake air temperature sensor (bank 2).

Fig 1: Identifying Mass Air Flow Sensor

Courtesy of NISSAN MOTOR CO., U.S.A.

REFERENCE DATA

Intake air temperature [°C (°F)]

Voltage⁽¹⁾ (V)

Resistance (kΩ)

25 (77)

3.3

1.800 - 2.200

80 (176)

1.2

0.283 - 0.359

⁽¹⁾	These data are reference values and are measured between ECM terminals 67 (Intake air temperature sensor) and 68 (Sensor ground).

Fig 2: Checking Resistance Between Engine Coolant Temperature Resistance Graph

Courtesy of NISSAN MOTOR CO., U.S.A.