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Home >> Lexus >> 2009 >> SC 430 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0351-U0001) - 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 OTHER DTC OUTPUT 

    Result

    Display (DTC output) Proceed to
    P2121 A
    P2121 and other DTCs B

    B → GO TO RELEVANT DTC CHART 

    A: Go to next step 

  2. REPLACE ACCELERATOR PEDAL 

    NEXT: Go to next step 

  3. CHECK OUTPUT DTC (ACCELERATOR PEDAL POSITION SENSOR DTCS ARE OUTPUT AGAIN) 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    2. Start the engine and allow the engine to idle for 15 seconds or more.
    3. Read DTCs.

      Result

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

    B → CHECK FOR INTERMITTENT PROBLEMS 

    A → REPLACE ECM