Engine Coolant Temperature Sensor

Check resistance as shown in the figure.

Fig 1: Checking Resistance Between Engine Coolant Temperature Sensor

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

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If NG, replace engine coolant temperature sensor.

Fig 2: DTC P0128 Thermostat Function - Temperature/Resistance Graph

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