METER / GAUGE SYSTEM Tachometer Malfunction

DESCRIPTION

In this circuit, the combination meter assembly receives engine speed signals from the ECM using the CAN communication system. The combination meter assembly displays the engine speed calculated based on the data received from the ECM.

WIRING DIAGRAM

A01G845E66

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication DTCs are output Click here.

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

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. PERFORM ACTIVE TEST USING GTS (TACHOMETER OPERATION)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS 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 OFF, 0, 1000, 2000, 3000, 4000, 5000, 6000, 7000 -
      OK
      Tachometer indication is normal.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  3. READ VALUE USING GTS (ENGINE RPM)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS 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

      610 to 710 rpm (for 2AR-FE): Idling

      600 to 700 rpm (for 2GR-FE): Idling

      		 -
      OK
      Engine speed displayed on the GTS is almost the same as the tachometer indication.

      Tech Tips


      • When the Data List values and tachometer values match, a signal output error 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.


    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

  4. CHECK SFI SYSTEM


    1. Check if SFI system DTCs are output Click here for 2AR-FE, Click here for 2GR-FE).

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output (for 2AR-FE). B
      DTCs are output (for 2GR-FE). C

    B

    GO TO SFI SYSTEM Click here

    C

    GO TO SFI SYSTEM Click here

    A

  5. READ VALUE USING GTS (ENGINE SPEED, ENGINE RPM)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus:


      1. for Engine and ECT: Powertrain / Engine and ECT / Data List.

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

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

      Engine and ECT
      Tester Display Measurement Item/Range Normal Condition Stored as Freeze Frame Data
      Engine Speed Engine speed/Min.: 0 rpm, Max.: 16383 rpm

      610 to 710 rpm (for 2AR-FE): Idling

      600 to 700 rpm (for 2GR-FE): Idling

      		 Yes

      Results of real-vehicle check:

      Idling (engine warmed up and A/C off): 660 rpm

      Diagnostic Note:

      When the crankshaft position sensor is malfunctioning, "Engine Speed" is approximately 0 rpm or varies greatly from the actual engine speed.
      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Engine Rpm Engine speed/Min.: 0 rpm, Max.: 12750 rpm

      610 to 710 rpm (for 2AR-FE): Idling

      600 to 700 rpm (for 2GR-FE): Idling

      		 -
      Result
      Result Proceed to
      The data list values of the ECUs do not match. A
      The data list values of the ECUs match (for 2AR-FE). B
      The data list values of the ECUs match (for 2GR-FE). C

      Tech Tips


      • 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 error of the ECM or an internal malfunction of the combination meter assembly is suspected.


    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

  6. REPLACE COMBINATION METER ASSEMBLY


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

      OK
      The operation of the tachometer returns to normal.
      Result
      Result Proceed to
      OK A
      NG (for 2AR-FE) B
      NG (for 2GR-FE) C

    B

    REPLACE ECM Click here

    C

    REPLACE ECM Click here

    A

    END