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Home >> Lexus >> 2009 >> IS 250 RWD, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS P0420 - 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. READ VALUE USING TECHSTREAM 
    1. Connect Techstream to the DLC3.
      Fig 1: Depressing And Releasing Accelerator Pedal
      GTY132854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG) and turn the tester on.
    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.
    4. Read the values displayed on the tester.

      Standard voltage

      Accelerator Pedal Operations Accel Sensor Out No. 1 Accel Sensor Out No. 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

    OK → See step   3 

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) 
    1. Disconnect the A26 Accelerator Pedal Position (APP) sensor connector.
      Fig 2: Identifying Connector Terminals
      GTY138465Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the A6 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Specified Condition
      VPA (A26-6) - VPA (A6-33) Below 1 Ω
      EPA (A26-5) - EPA (A6-34) Below 1 Ω
      VCPA (A26-4) - VCPA (A6-35) Below 1 Ω
      VPA2 (A26-3) - VPA2 (A6-32) Below 1 Ω
      EPA2 (A26-2) - EPA2 (A6-26) Below 1 Ω
      VCP2 (A26-1) - VCP2 (A6-27) Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection Specified Condition
      VPA (A26-6) or VPA (A6-33) - body ground 10 kΩ or higher
      EPA (A26-5) or EPA (A6-34) - body ground 10 kΩ or higher
      VCPA (A26-4) or VCPA (A6-35) - body ground 10 kΩ or higher
      VPA2 (A26-3) or VPA2 (A6-32) - body ground 10 kΩ or higher
      EPA2 (A26-2) or EPA2 (A6-26) - body ground 10 kΩ or higher
      VCP2 (A26-1) or VCP2 (A6-27) - body ground 10 kΩ or higher
    4. Reconnect the APP sensor connector.
    5. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY 

    NEXT: Go to next step 

  4. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the tester on.
    3. Clear DTCs. Refer to DTC CHECK / CLEAR .
    4. Start the engine.
    5. Allow the engine to idle for 15 seconds.
    6. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    7. Read DTCs.

      Result

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

    B → END 

    A → REPLACE ECM