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Home >> Toyota >> 2005 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control System (SFI) (1ZZ-FE (Fwd)) - Diagnostics >> SFI System (1ZZ-FE (Ff)) >> DTC P2120, P2122, P2123, P2125, P2127: Throttle/Pedal Position Sensor/Switch "D & E" Circuit Low/High Input >> Inspection Procedure
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Inspection Procedure

HINT:

Read freeze frame data using a hand-held tester or OBD II scan tool. Freeze frame data record the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data, from the time the malfunction occurred.

Hand-held tester: 

  1. READ VALUE USING HAND-HELD TESTER (ACCEL POS #1 AND ACCEL POS #2) 
    1. Connect a hand-held tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Select the following menu items: DIAGNOSIS/ENHANCED OBDII/DATA LIST/ALL/ACCEL POS #1 and ACCEL POS #2.
    4. Read the values displayed on the tester.

    Standard: 

    ACCELERATOR PEDAL OPERATION AND VOLTAGE SPECIFICATIONS

    Accelerator Pedal Operations ACCEL POS #1 (AP#1) ACCEL POS #2 (AP#2) Difference between AP#1 and AP#2
    1. Released 2. Depressed 3. Released Between 0.5V and 4.5V Between 1.2V and 5.0V More than 0.02 V

    OK: Go to step   6 

    Fig 1: Identifying Accelerator Pedal Depressed And Released Position
    G02661862Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: Go to next step. 

  2. INSPECT ACCELERATOR PEDAL ASSY (ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the A25 Accelerator Pedal Position (APP) sensor connector.
    2. Measure the resistance between each terminal.

      Standard: 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS

      Tester Connections Specified Conditions
      3-6 Between 1.5 kΩ and 6.0 kΩ at 20°C (68°F)
      1-4 Between 1.5 kΩ and 6.0 kΩ at 20°C (68°F)
    3. Reconnect the APP sensor connector.

    NG: REPLACE ACCELERATOR PEDAL ASSY (See  ACCELERATOR PEDAL ASSY (1ZZ-FE (FF))  ) 

    Fig 2: Measuring Resistance Between A25 Accelerator Pedal Position Sensor Connector Terminals
    G02661863Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step. 

  3. INSPECT ECM (VCPA AND VCP2 VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E6 ECM connector.

    Standard: 

    TESTER CONNECTION AND CONDITION SPECIFICATIONS

    Tester Connections Specified Conditions
    VCPA (E6-26) - EPA (E6-28) Between 4.5V and 5.5 V
    VCP2 (E6-27) - EPA2 (E6-29) Between 4.5V and 5.5 V

    NG: REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

    Fig 3: View Of E6 ECM Connector Terminal
    G02661864Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step. 

  4. INSPECT ECM (VPA AND VPA2 VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E6 ECM connector.

    Standard: 

    ACCELERATOR PEDAL OPERATION AND VOLTAGE SPECIFICATIONS

    Accelerator Pedal Operations Tester Connections Specified Conditions
    Released VPA (E6-22) - EPA (E6-28) Between 0.5V and 1.1 V
    Depressed VPA (E6-22) - EPA (E6-28) Between 2.6V and 4.5 V
    Released VPA2 (E6-23) - EPA2 (E6-29) Between 1.2V and 2.0 V
    Depressed VPA2 (E6-23) - EPA2 (E6-29) Between 3.4V and 5.3 V

    NG: Go to step 5 

    Fig 4: View Of E6 ECM Connector
    G02661865Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

  5. CHECK HARNESS AND CONNECTOR (ECM - ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the A25 APR sensor connector.
    2. Disconnect the E6 ECM connector.
    3. Check the resistance.

      Standard (Check for open): 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (FOR OPEN)

      Tester Connections Specified Conditions
      VPA1 (A25-5) - VPA (E6-22) Below 1 Ω
      EP1 (A25-3) - EPA (E6-28) Below 1 Ω
      VCP1 (A25-6) - VCPA (E6-26) Below 1 Ω
      VPA2 (A25-2) - VPA2 (E6-23) Below 1 Ω
      EP2 (A25-1) - EPA2 (E6-29) Below 1 Ω
      VCP2 (A25-4) - VCP2 (E6-27) Below 1 Ω

      Standard (Check for short): 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (FOR SHORT)

      Tester Connections Specified Conditions
      VPA1 (A25-5) or VPA (E6-22) - Body ground 10 kΩ or higher
      EP1 (A25-3) or EPA (E6-28) - Body ground 10 kΩ or higher
      VCP1 (A25-6) or VCPA (E6-26) - Body ground 10 kΩ or higher
      VPA2 (A25-2) or VPA2 (E6-23) - Body ground 10 kΩ or higher
      EP2 (A25-1) or EPA2 (E6-29) - Body ground 10 kΩ or higher
      VCP2 (A25-4) or VCP2 (E6-27) - Body ground 10 kΩ or higher
    4. Reconnect the APR sensor connector.
    5. Reconnect the ECM connector.
    Fig 5: View Of A25 APP Sensor Connector
    G02661866Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
    Fig 6: View Of E6 ECM Connector
    G02661867Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  6. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) 
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Clear DTCs (see DTC CHECK/CLEAR ).
    4. Allow the engine to idle for 15 seconds.
    5. Select the following menu items: DIAGNOSIS/ENHANCED OBD II/DTC INFO/CURRENT CODES.
    6. Read DTCs.

    Result: 

    DTC OUTPUT REFERENCE (DTC P2120/2122/2123/2125/2127/2128/2138)

    Display (DTC Output) Proceed To
    P2120, P2122, P2123, P2125, P2127, P2128 or P2138 A
    No output B

    B: (See  CHECK FOR INTERMITTENT PROBLEMS  ) 

    A 

    REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

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

  1. INSPECT ACCELERATOR PEDAL ASSY (ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the A25 Accelerator Pedal Position (APP) sensor connector.
    2. Measure the resistance between each terminal.

      Standard: 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (1 OF 2)

      Tester Connections Specified Conditions
      3-6 Between 1.5 kΩ and 6.0 kΩ at 20°C (68°F)
      1-4 Between 1.5 kΩ and 6.0 kΩ at 20°C (68°F)
    3. Reconnect the APP sensor connector.
    Fig 7: Measuring Resistance Between A25 Accelerator Pedal Position Sensor Connector Terminals
    G02661868Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: REPLACE ACCELERATOR PEDAL ASSY (See  ACCELERATOR PEDAL ASSY (1ZZ-FE (FF))  ) 

    OK: Go to next step. 

  2. INSPECT ECM (VCPA AND VCP2 VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E6 ECM connector.

      Standard: 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (2 OF 2)

      Tester Connections Specified Conditions
      VCPA (E6-26) - EPA (E6-28) Between 4.5V and 5.5 V
      VCP2 (E6-27) - EPA2 (E6-29) Between 4.5V and 5.5 V
    Fig 8: View Of E6 ECM Connector
    G02661869Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

    OK: Go to next step. 

  3. INSPECT ECM (VPA AND VPA2 VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the E6 ECM connector.

      Standard: 

      ACCELERATOR PEDAL OPERATION AND VOLTAGE SPECIFICATIONS

      Accelerator Pedal Operations Tester Connections Specified Conditions
      Released VPA (E6-22) - EPA (E6-28) Between 0.5V and 1.1 V
      Depressed VPA (E6-22) - EPA (E6-28) Between 2.6V and 4.5 V
      Released VPA2 (E6-23) - EPA2 (E6-29) Between 1.2V and 2.0 V
      Depressed VPA2 (E6-23) - EPA2 (E6-29) Between 3.4V and 5.3 V
    Fig 9: View Of E6 ECM Connector
    G02661870Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: Go to step   4 

    OK: REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

  4. CHECK HARNESS AND CONNECTOR (ECM - ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the A25 APR sensor connector.
    2. Disconnect the E6 ECM connector.
    3. Check the resistance.

      Standard (Check for open): 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (FOR OPEN)

      Tester Connections Specified Conditions
      VPA1 (A25-5) - VPA (E6-22) Below 1 Ω
      EP1 (A25-3) - EPA (E6-28) Below 1 Ω
      VCP1 (A25-6) - VCPA (E6-26) Below 1 Ω
      VPA2 (A25-2) - VPA2 (E6-23) Below 1 Ω
      EP2 (A25-1) - EPA2 (E6-29) Below 1 Ω
      VCP2 (A25-4) - VCP2 (E6-27) Below 1 Ω

      Standard (Check for short): 

      TESTER CONNECTION AND CONDITION SPECIFICATIONS (FOR SHORT)

      Tester Connections Specified Conditions
      VPA1 (A25-5) or VPA (E6-22) - Body ground 10 kΩ or higher
      EP1 (A25-3) or EPA (E6-28) - Body ground 10 kΩ or higher
      VCP1 (A25-6) or VCPA (E6-26) - Body ground 10 kΩ or higher
      VPA2 (A25-2) or VPA2 (E6-23) - Body ground 10 kΩ or higher
      EP2 (A25-1) or EPA2 (E6-29) - Body ground 10 kΩ or higher
      VCP2 (A25-4) or VCP2 (E6-27) - Body ground 10 kΩ or higher
    4. Reconnect the APP sensor connector.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 10: View Of APP Sensor Connector
    G02661871Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
    Fig 11: Disconnecting E6 ECM Connector
    G02661872Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step. 

  5. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS) 
    1. Connect an OBD II scan tool to the DLC3.
    2. Turn the ignition switch to ON and turn the scan tool ON.
    3. Clear DTCs using the scan tool.
    4. Allow the engine to idle for 15 seconds.
    5. Read DTCs using the scan tool.

    Result: 

    DTC OUTPUT REFERENCE (DTC P2120/2122/2123/2125/2127/2128/2138)

    Display (DTC Output) Proceed To
    P2120, P2122, P2123, P2125, P2127, P2128or P2138 A
    No output B

    B: (See  CHECK FOR INTERMITTENT PROBLEMS  ) 

    A: REPLACE ECM (See  ECM (1ZZ-FE/2ZZ-GE)  ) 

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