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Tachometer Malfunction [11/2017 - ]: Procedure

  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check if CAN communication DTCs are output.

      Refer to DIAGNOSIS SYSTEM [11/2017 - 10/2018] , or refer to DIAGNOSIS SYSTEM [10/2018 - 11/2019] , or refer to DIAGNOSIS SYSTEM [11/2019 - 09/2020] , or refer to DIAGNOSIS SYSTEM [09/2020 - 10/2022] , or refer to DIAGNOSIS SYSTEM [10/2022 - 10/2023] , or refer to DIAGNOSIS SYSTEM [10/2023 - ]

      Result

      Result Proceed to
      CAN communication DTCs are not output A
      CAN communication DTCs are output B

    Result: 

    B 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ] 

    Result: 

    A 

    See step  2

  2. CONFIRM MODEL 
    1. Choose the model to be inspected.

      Result

      Result Proceed to
      for Optitron Meter Type A
      for TFT Meter Type B

    Result: 

    B 

    See step  4

    Result: 

    A 

    See step  3

  3. PERFORM ACTIVE TEST USING TECHSTREAM (TACHOMETER OPERATION) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Combination Meter / Active Test.
    5. Perform the Active Test according to the display on the Techstream.

      Body Electrical > Combination Meter > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      TachoMeter Operation Tachometer OFF, 0, 1000, 2000, 3000, 4000, 5000, 6000 or 7000 -

      Body Electrical > Combination Meter > Active Test 

      Tester Display
      TachoMeter Operation

      OK

      Tachometer indication is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  4

  4. READ VALUE USING TECHSTREAM (ENGINE RPM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Combination Meter / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Combination Meter > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Engine Rpm Engine speed Min.: 0 rpm, Max.: 12750 rpm Almost the same as actual tachometer -

      Body Electrical > Combination Meter > Data List 

      Tester Display
      Engine Rpm

      OK

      Engine speed displayed on the Techstream is almost the same as the tachometer indication.

      HINT: 

      • When the Data List values and tachometer values match, a signal output malfunction of the ECM or an internal malfunction of the combination meter assembly is suspected.
      • When the Data List values and tachometer values do not match, an internal malfunction of the combination meter assembly is suspected.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  5

  5. CHECK FOR DTC 
    1. Check if SFI system DTCs are output.

      for 2GR-FKS: Refer to DTC CHECK / CLEAR [11/2017 - ]

      for 8AR-FTS: Refer to DTC CHECK / CLEAR [10/2015 - ]

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      SFI system DTCs are not output A
      SFI system DTCs are output B

    Result: 

    B 

    GO TO SFI SYSTEM 

    for 2GR-FKS: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - ]

    for 8AR-FTS: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ]

    Result: 

    A 

    See step  6

  6. READ VALUE USING TECHSTREAM (ENGINE SPEED, ENGINE RPM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus:
      1. for Engine: Powertrain / Engine / Data List.
      2. for Combination Meter: Body Electrical / Combination Meter / Data List.
    5. Read the Data List according to the display on the Techstream.
      1. Engine

        Powertrain > Engine > Data List 

        Tester Display Measurement Item Range Normal Condition Diagnostic Note
        Engine Speed Engine speed Min.: 0 rpm, Max.: 16383 rpm for 2GR-FKS:
        600 to 700 rpm: Idling (shift lever in N, engine warmed up and A/C off)
        for 8AR-FTS:
        750 to 850 rpm: Idling (shift lever in N, engine warmed up and A/C off)        		 When the crankshaft position sensor is malfunctioning, "Engine Speed" is approximately 0 rpm or varies greatly from the actual engine speed.

        Powertrain > Engine > Data List 

        Tester Display
        Engine Speed
      2. Combination Meter

        Body Electrical > Combination Meter > Data List 

        Tester Display Measurement Item Range Normal Condition Diagnostic Note
        Engine Rpm Engine speed Min.: 0 rpm, Max.: 12750 rpm Almost the same as actual tachometer -

        Body Electrical > Combination Meter > Data List 

        Tester Display
        Engine Rpm

        HINT: 

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

      Result

      Result Proceed to
      The Data List values of the ECUs do not match A
      The Data List values of the ECUs match B

    Result: 

    B 

    REPLACE ECM 

    for 2GR-FKS: Refer to REMOVAL [11/2017 - ]

    for 8AR-FTS: Refer to REMOVAL [10/2015 - ]

    Result: 

    A 

    See step  7

  7. REPLACE COMBINATION METER ASSEMBLY 
    1. Replace the combination meter assembly with a new one.

      Refer to REMOVAL [09/2014 - ]

      OK

      The operation of the tachometer returns to normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ECM 

    for 2GR-FKS: Refer to REMOVAL [11/2017 - ]

    for 8AR-FTS: Refer to REMOVAL [10/2015 - ]

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