METER / GAUGE SYSTEM Tachometer Malfunction

DESCRIPTION

In this circuit, the meter CPU receives engine speed signals from the ECM. The meter CPU displays the engine speed calculated based on the data received from the ECM.

WIRING DIAGRAM

A01DPZBE05
A01DOPME03

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication DTC is output.


      1. for LHD with Entry and Start System Click here.

      2. for LHD without Entry and Start System Click here.

      3. for RHD with Entry and Start System Click here.

      4. for RHD without Entry and Start System Click here.

        Result
        Result Proceed to
        CAN communication DTC is not output. A
        CAN communication DTC is output. (for LHD, with Entry and Start System) B
        CAN communication DTC is output. (for LHD, without Entry and Start System) C
        CAN communication DTC is output. (for RHD, with Entry and Start System) D
        CAN communication DTC is output. (for RHD, without Entry and Start System) E

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    D

    GO TO CAN COMMUNICATION SYSTEM Click here

    E

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK ENGINE TYPE


    1. Check the engine type.

      Engine Type
      Engine type Proceed to
      not 5L-E A
      5L-E B

    B

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER Click here

    A

  3. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (TACHO METER OPERATION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

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

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

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      Tacho Meter Operation Tachometer 0, 1000, 2000, 3000, 4000, 5000, 6000, 7000* (rpm) Confirm that the vehicle is stopped with the engine idling.

      • *: except 1KD-FTV

        OK
        Tachometer indication is normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  4. READ VALUE USING INTELLIGENT TESTER (ENGINE RPM)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body Electrical / Combination Meter / Data List.

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

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Engine Rpm Engine speed/Min.: 0 rpm, Max.: 12750 rpm 600 to 700 rpm (When idling) If the data received from the ECM exceeds the range that can be displayed on the meter, the meter continues to display the maximum value of the range.
      OK
      Engine speed displayed on the intelligent tester is almost the same as the tachometer indication.

    6. Record the engine speed displayed on the intelligent tester.

      Tech Tips

      Check the engine speed when the engine is fully warmed up and the air conditioning and all electrical accessories are off.


    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  5. READ VALUE USING INTELLIGENT TESTER (ENGINE SPEED)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List.

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

      Engine and ECT
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Engine Speed Engine speed/Min.: 0 rpm, Max.: 16383 rpm 600 to 700 rpm (When idling) -
      OK
      Engine speed displayed on the intelligent tester is almost the same as the previously recorded value displayed on the intelligent tester (Body Electrical / Combination Meter / Data List / Engine Rpm).
      Result
      Result Proceed to
      OK A
      NG (for 1GR-FE) B
      NG (for 2TR-FE) C
      NG (for 1KD-FTV, w/o DPF) D
      NG (for 1KD-FTV, w/ DPF) E

    B

    GO TO SFI SYSTEM Click here

    C

    GO TO SFI SYSTEM Click here

    D

    GO TO ECD SYSTEM Click here

    E

    GO TO ECD SYSTEM Click here

    A

  6. REPLACE ECM


    1. Replace the ECM with a new or normally functioning one.

      for 1GR-FE Click here.

      for 2TR-FE Click here.

      for 1KD-FTV Click here.

    2. Check the tachometer operation.

      OK
      The operation of the tachometer returns to normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    END

  7. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

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

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

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      Tacho Meter Operation Tachometer 0, 1000, 2000, 3000, 4000, 5000, 6000 (rpm) Confirm that the vehicle is stopped with the engine idling.
      OK
      Tachometer indication is normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  8. INSPECT WAVEFORM (ENGINE SPEED SIGNAL)


    1. Disconnect the G6 meter connector.

    2. A01DRX1E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)
      *b Speed Signal Waveform

      Using an oscilloscope, check the signal waveform.

      Measurement Condition
      Item Content
      Tester Connection G6-34 (S) - Body ground
      Tool Setting 5 V/DIV., 20 ms./DIV.
      Condition Idling with warm engine
      OK
      Waveform is output normally (refer to illustration).

      Tech Tips

      As the engine speed increases, the wavelength shortens.


    NG

    CHECK HARNESS AND CONNECTOR Click here

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

  9. CHECK HARNESS AND CONNECTOR


    1. Disconnect the G62 ECM connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      G62-7 (TACH) - G6-34 (S) Always Below 1 Ω
      G62-7 (TACH) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. REPLACE ECM


    1. Replace the ECM with a new or normally functioning one Click here.

      OK
      The operation of the tachometer returns to normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    END