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Home >> Lexus >> 2004 >> ES 330 >> Repair and Diagnosis >> External Pages >> Different car >> Section 302 (Engine Control System (SFI) - Diagnostics) >> DTC P2121: Throttle/Pedal Position Sensor/Switch "D" Circuit Range/Performance >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2005 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

Hand-held tester: 

  1. READ VALUE OF HAND-HELD TESTER (ACCEL POS #1 AND ACCEL POS #2) 
    Fig 1: Identifying Pedal Depressed Position
    G02628956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON.
    3. Select the item "DIAGNOSIS/ENHANCED OBD II/DATA LIST/ETCS/ACCEL POS #1 and ACCEL POS #2" and read its value displayed on the hand-held tester.

      Standard: 

      ACCELERATOR PEDAL SPECIFICATION

      Accelerator pedal ACCEL POS #1 ACCEL POS #2
      Released 0.5 to 1.1 V 1.2 to 2.0 V
      Depressed 2.6 to 4.5 V 3.4 to 5.3 V
    1. OK: CHECK AND REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    2. NG: GO TO NEXT STEP 
  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) 
    1. Disconnect the A15 accelerator pedal position sensor connector.
    2. Disconnect the E4 ECM connector.
    3. Check for continuity between the wire harness side connectors.
      Fig 2: Disconnecting A15 Accelerator Pedal Position Sensor Connector
      G02628957Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for open): 

      SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      VPA1 (A15-6) - VPA (E4-22) Continuity
      EPA (A15-5) - EPA (E4-28)
      VCPA (A15-4) - VCPA (E4-26)
      VPA2 (A15-3) - VPA2 (E4-23)
      EPA2 (A15-2) - EPA2 (E4-29)
      VCP2 (A15-1) - VCP2 (E4-27)
      Fig 3: Disconnecting E4 ECM Connector
      G02628958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for short): 

      SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      VPA1 (A15-6) or VPA (E4-22) - Body ground No continuity
      EPA (A15-5) or EPA (E4-28) - Body ground
      VCPA (A15-4) or VCPA (E4-26) - Body ground
      VPA2 (A15-3) or VPA2 (E4-23) - Body ground
      EPA2 (A15-2) or EPA2 (E4-29) - Body ground
      VCP2 (A15-1) or VCP2 (E4-27) - Body ground
    4. Reconnect the accelerator pedal position sensor connector.
    5. Reconnect the ECM connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE  ACCELERATOR PEDAL ROD ASSY 

OBD II scan tool (excluding hand-held tester): 

  1. INSPECT ECM (VPA AND VPA2 VOLTAGE) 
    Fig 4: Measuring Voltage Between Terminals Of E4 ECM Connector
    G02628959Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch ON.
    2. Measure the voltage between the terminals of the E4 ECM connector.

      Standard: 

      ACCELERATOR PEDAL POSITION SPECIFICATION TABLE

      Accelerator pedal position Symbols (Terminal No.) Symbols (Terminal No.)
      Accelerator pedal position VPA (E4-22) - EPA (E4-28) VPA2 (E4-23) - EPA2 (E4-29)
      Released 0.5 to 1.1 V 1.2 to 2.0 V
      Depressed 2.6 to 4.5 V 3.4 to 5.3 V
    1. OK: CHECK AND REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    2. NG: GO TO NEXT STEP 
  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM) 
    1. Disconnect the accelerator pedal position sensor connector.
    2. Disconnect the E4 ECM connector.
    3. Check for continuity between the wire harness side connectors.
      Fig 5: Disconnecting Accelerator Pedal Position Sensor Connector
      G02628960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for open): 

      SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      VPA1 (A15-6) - VPA (E4-22) Continuity
      EPA (A15-5) - EPA (E4-28)
      VCPA (A15-4) - VCPA (E4-26)
      VPA2 (A15-3) - VPA2 (E4-23)
      EPA2 (A15-2) - EPA2 (E4-29)
      VCP2 (A15-1) - VCP2 (E4-27)
      Fig 6: Disconnecting E4 ECM Connector
      G02628961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for short): 

      SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      VPA1 (A15-6) or VPA (E4-22) - Body ground No continuity
      EPA (A15-5) or EPA (E4-28) - Body ground
      VCPA (A15-4) or VCPA (E4-26) - Body ground
      VPA2 (A15-3) or VPA2 (E4-23) - Body ground
      EPA2 (A15-2) or EPA2 (E4-29) - Body ground
      VCP2 (A15-1) or VCP2 (E4-27) - Body ground
    4. Reconnect the accelerator pedal position sensor connector.
    5. Reconnect the ECM connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE  ACCELERATOR PEDAL ROD ASSY 
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