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DTC P2121: Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance [08/2016 - ]: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2121) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Trouble Codes.
    5. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTC P2121 is output A
      DTC P2121 and other DTCs are output B

      HINT: 

      If any DTCs other than P2121 are output, troubleshoot those DTCs first.

    Result: 

    B 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2016 - 11/2017]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2017 - 05/2018]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [05/2018 - 03/2019]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2019 - 09/2020]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2020 - 01/2023]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [01/2023 - ] 

    Result: 

    A 

    See step  2

  2. READ VALUE USING TECHSTREAM (ACCEL SENSOR OUT) 
    GTY453386Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Fully Depressed
    *b Fully Released
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Gas Throttle / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

      Powertrain > Engine > Data List 

      Tester Display
      Accel Sensor Out No. 1
      Accel Sensor Out No. 2
    5. Read the values displayed on the Techstream.

      Standard Voltage

      Accelerator Pedal Operation Accel Sensor Out No. 1 Accel Sensor Out No. 2
      Fully Released 0.5 to 1.1 V 1.2 to 2.0 V
      Fully Depressed 2.6 to 4.5 V 3.4 to 4.75 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [09/2014 - ] 

    Result: 

    NG 

    See step  3

  3. REPLACE ACCELERATOR PEDAL(W/SENSOR) ROD ASSEMBLY 
    1. Replace the accelerator pedal sensor assembly.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P2121) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - ]

      Powertrain > Engine > Clear DTCs 

    5. Turn the engine switch off and wait for at least 30 seconds.
    6. Turn the engine switch on (IG) and turn the Techstream on.
    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    8. Enter the following menus: Powertrain / Engine / Trouble Codes.
    9. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTC P2121 is output A
      DTCs are not output B

    Result: 

    A 

    REPLACE ECM. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    B 

    END 

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