METER / GAUGE SYSTEM Malfunction in Water Temperature Warning Light

DESCRIPTION

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

WIRING DIAGRAM

A003Y2PE43

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
    A
  2. SYSTEM CHECK


    1. Check the water temperature warning light.

      Result
      Result Proceed to
      Water temperature warning light does not come on. A
      Water temperature warning light remains on. B

    B
    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 Water temperature warning light OFF or ON -
      OK
      Water temperature warning light operation is normal.

    NG
    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
    C
    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 / Combination Meter / Data List.

      2. for Engine: Powertrain / Engine and ECT / 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: 75 to 100°C (167 to 212°F) -
    6. Check the values by referring to the table below.

      Engine and ECT
      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: 75 to 100°C (167 to 212°F)
      • After warming up the engine: the engine coolant temperature 75 to 100°C (167 to 212°F).

      • If the value is -40°C (-40°F) or 140°C (284°F), the sensor circuit open or shorted.

      Note

      Enter the inspection mode Click here.

      Result
      Result Proceed to
      The data list values of the ECUs do not match. OK
      The data list values of the ECUs match. NG

      Tech Tips

      When the Data List values of the ECUs do not match, a signal output error of the ECM is suspected.


    NG
    OK
  6. REPLACE COMBINATION METER ASSEMBLY


    1. Replace the combination meter assembly with a new or a known good one Click here.

      OK
      The operation of the water temperature warning light returns to normal.

    NG
    OK