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Home >> Toyota >> 2009 >> Prius Base >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> P112 Hybrid Vehicle Control - DTC P0AA1 - P3226, DTC U0100 - U0146 >> DTC P2122-104 Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input; DTC P2123-105 Throttle / Pedal Position Sensor / Switch "D" Circuit High Input; DTC P2127-107 Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input; DTC P2128-108 Throttle / Pedal Position Sensor / Switch "E" Circuit High Input >> Inspection Procedure
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Inspection Procedure

  1. READ VALUE OF THE TECHSTREAM (ACCEL PEDAL POS #1 AND ACCEL PEDAL POS #2) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch ON (IG).
    3. Enter the following menus: Powertrain / Engine Control / Data List.
    4. Read the "Accel Pedal Pos #1" and "Accel Pedal Pos #2" values on the Techstream with the engine stopped.

      OK: Changes with accelerator pedal pressure 

    OK:  Go to step  5

    Fig 1: Depressing And Releasing Accelerator Pedal Position
    G05674789Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the H16 HV control ECU connector.
      Fig 2: Disconnecting H16 HV Control ECU Connector
      G05674790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the A13 accelerator pedal position sensor connector.
    3. Turn the power switch ON (IG).
    4. Measure the voltage between the terminals of the HV control ECU connector and body ground.
      Fig 3: Identifying A13 Accelerator Pedal Position Sensor Connector Terminals
      G05674791Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      VPA1 (H16-26) - Body ground Below 1 V
      VCP1 (H16-25) - Body ground Below 1 V
      EP1 (H16-27) - Body ground Below 1 V
      VPA2 (H16-34) - Body ground Below 1 V
      VCP2 (H16-33) - Body ground Below 1 V
      EP2 (H16-35) - Body ground Below 1 V
    5. Turn the power switch OFF.
    6. Measure the resistance between the wire harness side connectors.

      Standard resistance (Check for open) 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      VPA1 (H16-26) - VPA (A13-6) Below 1 Ω
      VCP1 (H16-25) - VCPA (A13-4) Below 1 Ω
      EP1 (H16-27) - EPA (A13-5) Below 1 Ω
      VPA2 (H16-34) - VPA2 (A13-3) Below 1 Ω
      VCP2 (H16-33) - VCP2 (A13-1) Below 1 Ω
      EP2 (H16-35) - EPA2 (A13-2) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      VPA1 (H16-26) or VPA (A13-6) - Body ground 10 kΩ or higher
      VCP1 (H16-25) or VCPA (A13-4) - Body ground 10 kΩ or higher
      EP1 (H16-27) or EPA (A13-5) - Body ground 10 kΩ or higher
      VPA2 (H16-34) or VPA2 (A13-3) - Body ground 10 kΩ or higher
      VCP2 (H16-33) or VCP2 (A13-1) - Body ground 10 kΩ or higher
      EP2 (H16-35) or EPA2 (A13-2) - Body ground 10 kΩ or higher
    7. Reconnect the accelerator pedal position sensor connector.
    8. Reconnect the HV control ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  3. INSPECT HYBRID VEHICLE CONTROL ECU (VCP1 OR VCP2 VOLTAGE) 
    1. Disconnect the A13 accelerator pedal position sensor connector.
    2. Turn the power switch ON (IG).
      Fig 4: Identifying Accelerator Pedal Position Sensor Connector
      G05674792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the voltage between the terminals of the HV control ECU connector.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      VCP1 (H16-25) - EP1 (H16-27) 4.5 to 5.5 V
      VCP2 (H16-33) - EP2 (H16-35) 4.5 to 5.5 V
    4. Reconnect the accelerator pedal position sensor connector.

    NG: REPLACE HYBRID VEHICLE CONTROL ECU 

    Fig 5: Identifying HV Control ECU Connector
    G05674793Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. REPLACE ACCELERATOR PEDAL ROD 
    1. Replace the Accelerator pedal rod (see REMOVAL ).
  5. CHECK IF DTC OUTPUT RECURS (DTC P2122, P2123, P2127 OR P2128) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch ON (IG).
    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
    4. Perform a simulation test.
    5. Check if DTCs are output.

      Result: 

      DTC P2122, P2123, P2127 or P2128 is not output again 

    YES: SYSTEM IS OK 

    NO: REPLACE HYBRID VEHICLE CONTROL ECU