METER / GAUGE SYSTEM Engine Coolant Temperature Gauge Malfunction

DESCRIPTION

In this circuit, the combination meter assembly receives engine coolant temperature signals from the ECM using CAN communication lines. The combination meter assembly displays an engine coolant temperature that is calculated based on the data received from the ECM.

WIRING DIAGRAM

A004OS4E01
*1 Combination Meter Assembly
*2 CAN Communication Line

CAUTION / NOTICE / HINT

Tech Tips

If there is an open or short in the engine coolant temperature sensor circuit, an ECD system DTC is output. If an ECD system DTC is output, perform troubleshooting for the ECD system first.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check for DTCs Click here.

      Result
      Result Proceed to
      CAN communication system DTC is not output A
      CAN communication system DTC is output B

    B

    Go to CAN COMMUNICATION SYSTEM Click here

    A

  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (COOLANT TEMP)


    1. Use the Active Test to check the operation of the engine coolant temperature receiver gauge Click here.

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      Water Temperature Meter Operation Engine coolant temperature receiver gauge LOW, NORMAL or HIGH Perform the test with the vehicle stopped and the engine idling.

      Tech Tips

      Confirm that the vehicle is stopped and the engine is idling.

      OK
      Needle indication is normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  3. READ VALUE USING INTELLIGENT TESTER (ENGINE COOLANT TEMPERATURE)


    1. Use the Data List to check if the engine coolant temperature receiver gauge is operating properly Click here.

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temperature Engine coolant temperature/Min.: -40 (-40), Max.: 127.5 (261.5) After warming up: 80 to 95 (176 to 203)

      • Unit: °C (°F)

      • If the value is -40 (-40), the sensor circuit is open.

      • If the value is 127.5 (261.5), the sensor circuit is shorted.
      OK
      Coolant temperature displayed on the intelligent tester is between 80°C (176°F) and 95°C (203°F) after warming up.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  4. READ VALUE USING INTELLIGENT TESTER (ENGINE COOLANT TEMPERATURE)


    1. Use the Data List to check if the engine coolant temperature sensor is operating properly Click here.

      Engine
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temp Engine coolant temperature/Min.: -40°C (-40°F), Max.: 140°C (284°F) After warming up: 80 to 100°C (176 to 212°F)

      • If the value is -40°C (-40°F), the sensor circuit is open.

      • If the value is 140°C (284°F), the sensor circuit is shorted.
      OK
      Engine coolant temperature value displayed on the intelligent tester is almost the same as actual engine coolant temperature.
      Result
      Result Proceed to
      OK A
      NG (for 1AD-FTV) B
      NG (for 2AD-FHV) C
      NG (for 2AD-FTV) D

    B

    CHECK VEHICLE TYPE Click here

    C

    Go to ECD SYSTEM Click here

    D

    CHECK VEHICLE TYPE Click here

    A

  5. REPLACE COMBINATION METER ASSEMBLY


    1. Temporarily replace the combination meter with a new one or normally functioning one Click here.


    NEXT

  6. CHECK COMBINATION METER ASSEMBLY


    1. Check that the operation of the combination meter returns to normal Click here.

      OK
      Operation of combination meter returns to normal.
      Result
      Result Proceed to
      OK A
      NG (for 1AD-FTV) B
      NG (for 2AD-FHV) C
      NG (for 2AD-FTV) D

    A

    END (COMBINATION METER IS DEFECTIVE)

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    D

    REPLACE ECM Click here

  7. CHECK VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      for CCo A
      for DPF B

    A

    Go to ECD SYSTEM Click here

    B

    Go to ECD SYSTEM Click here

  8. CHECK VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      w/ Gear Shift Indicator A
      w/o Gear Shift Indicator B

    A

    Go to ECD SYSTEM Click here

    B

    Go to ECD SYSTEM Click here