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Home >> Infiniti >> 2004 >> FX35 AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P0117 & P0118 ECT Sensor >> Component Description
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Component Description

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 Engine Coolant Temperature Sensor Components
G00729387Courtesy of NISSAN MOTOR CO., U.S.A.

< Reference data > 

For engine coolant temperature sensor specifications, see Fig 2 and for graph of thermistor performance, see Figure.

Fig 2: Identifying Engine Coolant Temperature Sensor Thermistor Specifications
G00729388Courtesy of NISSAN MOTOR CO., U.S.A.
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.