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Engine Coolant Temperature (ECT) Sensor

NOTE: When inspecting ECT sensor in water, prevent water flow into terminals. After inspection, wipe ALL water from sensor.
  1. Remove ECT sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION article.
  2. Place probe end of ECT sensor and thermometer in container of water. Attach ohmmeter between electrical terminals on ECT sensor. Heat water and check that resistance is within specification in relation to temperature. See Fig 1. Replace ECT sensor if resistance is not within specification.
Fig 1: Testing Engine Coolant Temperature (ECT) Sensor Resistance
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