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Home >> Lexus >> 2010 >> SC 430 >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System (Diagnostic Codes (P0010-P0340) >> SFI System >> DTC P0115: Engine Coolant Temperature Circuit; DTC P0117: Engine Coolant Temperature Circuit Low Input; DTC P0118: Engine Coolant Temperature Circuit High Input >> Procedure
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DTC P0115: Engine Coolant Temperature Circuit; DTC P0117: Engine Coolant Temperature Circuit Low Input; DTC P0118: Engine Coolant Temperature Circuit High Input: Procedure

  1. READ VALUE USING TECHSTREAM (ENGINE COOLANT TEMPERATURE) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON and turn the Techstream on.
    3. Enter the following menus: Powertrain / Engine / Coolant Temp.
    4. Read the values.

      OK

      Same value as the actual ECT

      Result

      Result Proceed to
      -40°C (-40°F) A
      140°C (284°F) or more B
      OK (same as present temperature) C

      HINT: 

      If there is an open circuit, the Techstream indicates -40°C (-40°F).

      If there is a short circuit, the Techstream indicates 140°C (284°F) or more.

    C → CHECK FOR INTERMITTENT PROBLEMS 

    B → See step   4 

    A: Go to next step 

  2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) 
    Fig 1: Identifying E7 ECT Sensor Connector Terminals
    GTY145263Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E7 ECT sensor connector.
    2. Connect terminals 1 and 2 of the ECT sensor wire harness side connector.
    3. Turn the ignition switch to ON.
    4. Read the value.

      Standard

      Temperature value is 140°C (284°F) or more

    NG → See step   3 

    OK → CONFIRM GOOD CONNECTION AT SENSOR. IF OK, REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

  3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM) 
    Fig 2: Identifying THW Of E4 ECM And E2 Of E2 ECM Connector Terminals
    GTY145259Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E7 ECT sensor connector.
    2. Connect terminal THW of the E4 ECM connector and terminal E2 of the E2 ECM connector.

      HINT: 

      Before checking, do a visual and contact pressure check for the ECM connector.

    3. Turn the ignition switch to ON.
    4. Read the value.

      Standard

      Temperature value is 140°C (284°F) or more

    NG → CONFIRM GOOD CONNECTION AT ECM. IF OK, REPLACE ECM 

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR 

  4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
    Fig 3: Checking E7 ECT Sensor And ECM Wire Harness
    GTY144947Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E7 ECT sensor connector.
    2. Turn the ignition switch to ON.
    3. Read the value.

      Standard

      Temperature value is -40°C (-40°F)

    NG → See step   5 

    OK → REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

  5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
    Fig 4: Disconnecting E2 And E4 ECM Connector Terminals
    GTY145261Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E7 ECT sensor connector.
    2. Disconnect the E2 and E4 ECM connectors.
    3. Turn the ignition switch to ON.
    4. Read the value.

      Standard

      Temperature value is -40°C (-40°F)

    NG → REPLACE ECM 

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - ENGINE COOLANT TEMPERATURE SENSOR)