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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> DTC P0125: ECT Sensor >> Component Description
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Component Description

NOTE: If DTC P0125 is displayed with P0117 or P0118, first perform trouble diagnosis for DTC P0117, P0118, see DTC P0117, P0118 ECT SENSOR .

The engine coolant temperature sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the engine coolant 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.

Fig 1: Identifying ECT Sensor
G00776978Courtesy of NISSAN MOTOR CO., U.S.A.

< Reference data> 

Fig 2: ECT Sensor Reference Data
G00776979Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 3: ECT Sensor Reference Graph
G00776980Courtesy of NISSAN MOTOR CO., U.S.A.
CAUTION: Do not use ECM ground terminals when measuring input/output voltage. Doing so may damage the ECM's transistor. Use ground other than ECM, such as body ground.