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Component Description

WARNING: This page is about a different car, the 2004 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.

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.See Figure .

Fig 1: Identifying Engine Coolant Temperature Sensor
G00786581Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Engine Coolant Temperature/Voltage/Resistance Specifications
G00786582Courtesy of NISSAN MOTOR CO., U.S.A.

*: These data are reference values and are measured between ECM terminal 93 (Engine coolant temperature sensor) and ground.

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.