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Inspection Procedure

HINT:

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

  1. READ VALUE OF INTELLIGENT TESTER (ACCEL POS #1 AND ACCEL POS #2) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch on (IG) and turn the tester on.
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / ACCEL POS #1 and ACCEL POS #2.
    4. Read the values displayed on the tester.

      Standard voltage 

      ACCELERATOR PEDAL OPERATIONS

      Accelerator Pedal Operations ACCEL POS #1 (AP#1) ACCEL POS #2 (AP#2)
      Released 0.5 to 1.1 V 1.2 to 2.0 V
      Depressed 2.6 to 4.5 V 3.4 to 5.0 V
      Fig 1: Pressing Accelerator Pedal
      G04375084Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step   4 

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) 
    1. Disconnect the A19 Accelerator Pedal Position (APP) sensor connector.
    2. Disconnect the A24 ECM connector.
    3. Measure the resistance.

      Standard resistance (Check for open) 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      VPA (A19-6) - VPA (A24-18) Below 1
      EPA (A19-5) - EPA (A24-20) Below 1
      VCPA (A19-4) - VCPA (A24-26) Below 1
      VPA2 (A19-3) - VPA2 (A24-19) Below 1
      EPA2 (A19-2) - EPA2 (A24-21) Below 1
      VCP2 (A19-1) - VCP2 (A24-27) Below 1

      Standard resistance (Check for short) 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      VPA (A19-6) or VPA (A24-18) - Body ground 10 k or higher
      EPA (A19-5) or EPA (A24-20) - Body ground 10 k or higher
      VCPA (A19-4) or VCPA (A24-26) - Body ground 10 k or higher
      VPA2 (A19-3) or VPA2 (A24-19) - Body ground 10 k or higher
      EPA2 (A19-2) or EPA2 (A24-21) - Body ground 10 k or higher
      VCP2 (A19-1) or VCP2 (A24-27) - Body ground 10 k or higher
    4. Reconnect the APP sensor connector.
    5. Reconnect the ECM connector.
      Fig 2: Disconnecting A24 ECM Connector
      G04375085Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  3. REPLACE ACCELERATOR PEDAL 
    1. Replace the accelerator pedal (See REMOVAL ).

    NEXT 

  4. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch on (IG) and turn the tester on.
    3. Clear DTCs (See DTC CHECK / CLEAR ).
    4. Start the engine.
    5. Allow the engine to idle for 15 seconds.
    6. Select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
    7. Read DTCs.

      Result 

      RESULT REFERENCE CHART

      Display (DTC Output) Proceed to
      P2121 A
      No output B

    B: SYSTEM OK 

    A: REPLACE ECM