METER / GAUGE SYSTEM Engine Coolant Temperature Gauge Malfunction

DESCRIPTION

In this circuit, the No. 1 meter ECU receives engine coolant temperature signals from the ECM using CAN communication lines. The No. 1 meter ECU displays an engine coolant temperature that is calculated based on the data received from the ECM.

WIRING DIAGRAM

A01GJ3FE01

INSPECTION PROCEDURE

Tech Tips

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

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check the DTC Click here.

      Result:
      Result Proceed to
      CAN communication system DTC is not output A
      CAN communication system (for LHD) DTC is output B
      CAN communication system (for RHD) DTC is output C

    B

    Go to CAN COMMUNICATION SYSTEM Click here

    C

    Go to CAN COMMUNICATION SYSTEM Click here

    A

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


    1. Operate the intelligent tester according to the display and select "Active Test".

      Combination Meter:
      Tester Display Test Part Control Range
      Water Temperature Meter Operation Engine coolant temperature receiver gauge LOW / NORMAL / HI

      Tech Tips

      Confirm that the vehicle is stopped and engine is idling.

      OK
      Needle indication is normal.

    NG

    REPLACE NO. 1 METER ECU

    OK

  3. READ VALUE USING INTELLIGENT TESTER (COOLANT TEMPERATURE)


    1. Operate the intelligent tester according to the display and select "Data List".

      Combination Meter:
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temperature Engine coolant temperature / Min.: -40 (-40), Max.: 140 (284 ) After warming up: 80 to 105 (176 to 221)

      • Unit: °C (°F)

      • If value -40 (-40): sensor circuit open

      • If value 140 (284): sensor circuit shorted
      OK
      Coolant temperature displayed on tester is between 80°C (176°F) and 95°C (203°F) after warming up.

    NG

    READ VALUE USING INTELLIGENT TESTER (WATER TEMPERATURE) Click here

    OK

    REPLACE NO. 1 METER ECU

  4. READ VALUE USING INTELLIGENT TESTER (WATER TEMPERATURE)


    1. Operate the intelligent tester according to the display and select "Data List".

      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) -
      OK
      Engine coolant temperature value displayed on tester is almost the same as actual engine coolant temperature.
      Result:
      Result Proceed to
      Result is as specified A
      Result is not as specified (for 1UR-FSE) B
      Result is not as specified (for 1UR-FE) C

    B

    Go to SFI SYSTEM Click here

    C

    Go to SFI SYSTEM Click here

    A

  5. REPLACE NO. 1 METER ECU


    1. Temporarily replace the No. 1 meter ECU with a new one.


    NEXT

  6. CHECK NO.1 METER ECU (OPERATION)


    1. Check the operation of the No. 1 meter ECU returns to normal Click here.

      Result:
      Result Proceed to
      Operation of No. 1 meter ECU returns to normal A
      Operation of No. 1 meter ECU does not return to normal (1UR-FSE) B
      Operation of No. 1 meter ECU does not return to normal (1UR-FE) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

    END (NO. 1 METER ECU IS DEFECTIVE)