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Engine Coolant Temperature (ECT) Sensor

  1. Ensure ignition is off. Note location of ECT sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION  table. Remove ECT sensor.
  2. Place probe end of ECT sensor and thermometer in container of water. Attach ohmmeter between ECT sensor terminals. Heat water and note that resistance is within specification in relation to temperature. See Fig 1. Replace ECT sensor if resistance is not within specification.
  3. Using NEW gasket, install ECT sensor. Tighten ECT sensor to 15 ft. lbs. (20 N.m). Fill cooling system.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION

Model Location
ES300 On Coolant Housing In Front Of Intake Manifold, At Timing Belt End Of Engine & Contains Dark Gray 2-Pin Connector With Green/Black & Brown Wires
RX300 On Coolant Housing In Front Of Intake Manifold, At Timing Belt End Of Engine & Contains Dark Gray 2-Pin Connector With Green/White & Brown Wires
Fig 1: Testing Engine Coolant Temperature (ECT) Sensor
G95D32501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002