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Home >> Lexus >> 2012 >> IS F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P1604-U0101) & Circuit Tests)) >> SFI System >> DTC P2121: Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance >> Procedure
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DTC P2121: Throttle / Pedal Position Sensor / Switch "D" Circuit Range / Performance: 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 DTCs.

      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.

    B → See step   7 

    A: Go to next step 

  2. READ VALUE USING TECHSTREAM (ACCEL POSITION SENSOR OUT) 
    1. Connect the Techstream to the DLC3.
      Fig 1: View Of Depressing And Releasing Accelerator Pedal
      GTY251145Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG) and turn the Techstream on.
    3. Enter the following menus: Powertrain / Engine / Data List / All Data / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.
    4. Read the value 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 4.98 V

    NG → See step   3 

    OK → See step   6 

  3. REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY 
    1. Replace the accelerator pedal sensor assembly. Refer to REMOVAL .

    NEXT: Go to next step 

  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P2121) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the Techstream on.
    3. Clear DTC. Refer to DTC CHECK / CLEAR .
    4. Turn the engine switch off and wait for at least 30 seconds.
    5. Turn the engine switch on (IG) and turn the Techstream on.
    6. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
    7. Enter the following menus: Powertrain / Engine / Trouble Codes.
    8. Read the DTCs.

      Result

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

    B → END 

    A → See step   5 

  5. REPLACE ECM. Refer to  REMOVAL 
  6. CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS 
  7. GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART