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Malfunction in Water Temperature Warning Light [06/2015 - ]: Procedure

  1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM) 
    1. Check for DTCs.

      Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2015 - 11/2018] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - ]

      OK

      No DTCs are output.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2015 - 11/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK FOR DTC (FC SYSTEM) 
    1. Check for DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Powertrain > FC > Trouble Codes 

      OK

      No DTCs are output.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO FC CONTROL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2015 - ] 

    Result: 

    OK 

    See step  3

  3. PERFORM ACTIVE TEST USING TECHSTREAM (INDICAT. LAMP COOLANT HOT) 
    1. Using the Techstream, perform the Active Test.

      Refer to DATA LIST / ACTIVE TEST [06/2015 - 01/2018] , or refer to DATA LIST / ACTIVE TEST [01/2018 - 11/2018] , or refer to DATA LIST / ACTIVE TEST [11/2018 - ]

      Body Electrical > Combination Meter > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      Indicat. Lamp Coolant Hot Water temperature hot warning light OFF or ON -

      Body Electrical > Combination Meter > Active Test 

      Tester Display
      Indicat. Lamp Coolant Hot

      OK

      Value selected during Active Test is displayed.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

    Result: 

    OK 

    See step  4

  4. READ VALUE USING TECHSTREAM (FC STACK COOLANT TEMPERATURE (FC OUTLET), FC COOLANT TEMPERATURE) 
    1. Using the Techstream, read the Data List.

      Refer to DATA LIST / ACTIVE TEST [06/2015 - 01/2018] , or refer to DATA LIST / ACTIVE TEST [01/2018 - 11/2018] , or refer to DATA LIST / ACTIVE TEST [11/2018 - ]

      Powertrain > FC > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FC Stack Coolant Temperature (Radiator Outlet) FC coolant temperature Min.: -40°C (-40°F), Max: 215°C (419°F) 50 to 85°C (122 to 185°F): After warming up the engine -

      Body Electrical > Combination Meter > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FC Coolant Temperature FC Stack coolant temperature Min.: 0°C (0°F), Max.: 127.5°C (261.5°F) 50 to 85°C (122 to 185°F): After warming up the engine -

      Powertrain > FC > Data List 

      Tester Display
      FC Stack Coolant Temperature (Radiator Outlet)

      Body Electrical > Combination Meter > Data List 

      Tester Display
      FC Coolant Temperature

      HINT: 

      • When the Data List values of the ECUs match, an internal malfunction of the FC control ECU is suspected.
      • When the Data List values of the ECUs do not match, a signal output error of the FC control ECU or an internal malfunction of the combination meter assembly is suspected.

      OK

      The Data List values of the ECUs do not match.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FC CONTROL ECU. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ] 

    Result: 

    OK 

    See step  5

  5. CHECK COMBINATION METER ASSEMBLY 
    1. Replace the combination meter assembly.

      Refer to REMOVAL [06/2015 - 11/2018] , or refer to REMOVAL [11/2018 - ]

    2. Check that the operation of the water temperature warning returns to normal.

      OK

      The operation of the water temperature warning returns to normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (COMBINATION METER ASSEMBLY IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE FC CONTROL ECU. Refer to  REMOVAL [06/2015 - 11/2018]  , or refer to  REMOVAL [11/2018 - ]