Component Description

WARNING: This page is about a different car, the 2004 Infiniti FX45. 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.

Fig 1: Identifying Engine COOLANT Temperature Sensor Components

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

Reference data

Fig 2: Identifying Engine COOLANT Temperature Sensor Thermistor Specifications

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

For thermistor specifications in graph format, see Figure .

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.