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Home >> Nissan-Datsun >> 2005 >> Sentra SE-R >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 2 (Engine Control System (QG18DE)) >> DTC P0117, P0118: ECT Sensor >> Component Description
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Component Description

WARNING: This page is about a different variant/trim than selected.

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
G02449801Courtesy of NISSAN MOTOR CO., U.S.A.

Reference data 

Fig 2: ECT Sensor Temperature Versus Resistance Graph
G02449802Courtesy of NISSAN MOTOR CO., U.S.A.
ECT SENSOR RESISTANCE/VOLTAGE SPECIFICATIONS

Engine coolant temperature °C (°F) Voltage(1)V Resistance kΩ
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
(1) These data are reference values and are measured between ECM terminal 73 (Engine coolant temperature sensor) and ground.
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.