METER / GAUGE SYSTEM Malfunction in Water Temperature Warning Light

DESCRIPTION

In this circuit, the meter ECU (meter circuit plate No.3) receives engine coolant temperature signals from the ECM using the CAN communication system (CAN No. 1 Bus). The meter ECU (meter circuit plate No.3) displays engine coolant temperature that is calculated based on the data received from the ECM.

WIRING DIAGRAM

A01JCCLE25

INSPECTION PROCEDURE

Tech Tips


  • If there is an open or short in the engine coolant temperature sensor circuit, the ECM stores the DTCs. Troubleshoot the SFI System Click here.

  • If the exhaust heat recirculation system has a malfunction, the engine coolant temperature hot warning light comes on to inform the driver of the malfunction.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication DTC is output Click here.

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

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. SYSTEM CHECK


    1. Check the coolant hot warning light.

      Result
      Result Proceed to
      Coolant hot warning light does not come on. A
      Coolant hot warning light remains on. B

    B

    CHECK FOR DTC Click here

    A

  3. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (COOLANT HOT INDICATOR)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Combination Meter / Active Test.

    5. Check the operation by referring to the table below.

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      Coolant Hot Indicator Coolant hot warning light OFF or ON Confirm that the vehicle is stopped with the engine idling
      OK
      Coolant hot warning light operation is normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY (NO. 3 METER CIRCUIT PLATE)

    OK

  4. CHECK FOR DTC


    1. Check for the DTC.

      Result
      Result Proceed to
      No DTC is output. A
      DTC P0115 is output. B
      DTC B1503 is output. C

    B

    GO TO SFI SYSTEM

    C

    GO TO METER / GAUGE SYSTEM

    A

  5. READ VALUE USING INTELLIGENT TESTER (COOLANT TEMPERATURE, COOLANT TEMP)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

    4. Enter the following menus:


      1. for Combination Meter: Body Electrical / Combination Meter / Data List.

      2. for Engine: Powertrain / Engine / Data List.

    5. Check the values by referring to the table below.

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temperature Engine coolant temperature/-40 to 127.5°C (-40 to 261.5°F) After warming up: 80 to 100°C (176 to 212°F) -

    6. Check the values by referring to the table below.

      Engine
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temp Engine coolant temperature/Min.: -40°C (-40°F), Max.: 215°C (419°F) After warming up: 80 to 100°C (176 to 212°F)

      • If -40°C (-40°F): sensor circuit open

      • If 140°C (284°F) or more: sensor circuit shorted
      OK
      When the Data List values of the ECUs do not match, a signal output error of the ECM is suspected.

    NG

    REPLACE ECM

    OK

  6. REPLACE COMBINATION METER ASSEMBLY (NO. 3 METER CIRCUIT PLATE)


    1. Replace the combination meter assembly (No. 3 meter circuit plate) with a new or a known good one Click here.

      OK
      The operation of the coolant hot warning light returns to normal.

    NG

    REPLACE ECM

    OK

    END