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Home >> Toyota >> 2006 >> Matrix XRS >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control System (2ZZ-GE) >> SFI System >> DTC P0120 Throttle / Pedal Position Sensor / Switch "A" Circuit; DTC P0122 Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input; DTC P0123 Throttle / Pedal Position Sensor / Switch "A" Circuit High Input >> Inspection Procedure
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Inspection Procedure

HINT:

When using intelligent tester: 

  1. READ VALUE OF INTELLIGENT TESTER (THROTTLE VALVE OPENING PERCENTAGE) 
    1. Connect an intelligent tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ETCS / THROTTLE POS.
    4. Read the value displayed on the tester when the accelerator pedal is released and depressed.

      Result 

      RESULT REFERENCE

      Throttle Valve Opening Angle (%) Proceed to
      0 (constant) A
      From approximately 0 to 75 B
      Approximately 100 (constant) C
      Fig 1: Identifying Released And Depressed Accelerator Pedal
      G04460589Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: CHECK FOR INTERMITTENT PROBLEMS 

    C: Go to step   4 

    A: Go to Next Step 

  2. INSPECT THROTTLE POSITION SENSOR 
    1. Disconnect the T1 Throttle Position (TP) sensor connector.
    2. Measure the resistance between the terminals of the TP sensor.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connections Throttle Valve Positions Specified Conditions
      VC (T1-2) - E2 (T1-1) - Between 2.5 k and 5.9 k
      VTA (T1-3) - E2 (T1-1) Fully closed Between 0.2 k and 5.7 k
      VTA (T1-3) - E2 (T1-1) Fully open Between 2.0 k and 10.2 k
    3. Reconnect the TP sensor connector.

    NG: REPLACE THROTTLE POSITION SENSOR 

    Fig 2: Identifying T1 Throttle Position (TP) Sensor Connector Terminals
    G04460590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  3. CHECK HARNESS AND CONNECTOR (ECM - THROTTLE POSITION SENSOR) 
    1. Disconnect the E3 ECM connector.
    2. Measure the resistance between the terminals of the ECM connector.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connections Throttle Valve Positions Specified Conditions
      VC (E3-18) - E2 (E3-28) - Between 2.5 k and 5.9 k
      VTA (E3-21) - E2 (E3-28) Fully closed Between 0.2 k and 5.7 k
      VTA (E3-21) - E2 (E3-28) Fully open Between 2.0 k and 10.2 k
      Fig 3: Disconnecting E3 ECM Connector
      G04460591Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance.

      Standard resistance (Check for short) 

      RESISTANCE SPECIFIED CONDITIONS (FOR SHORT)

      Tester Connections Specified Conditions
      VC (E3-18) - Body ground 10 k or higher
      VTA (E3-28) - Body ground 10 k or higher
    4. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM 

  4. INSPECT THROTTLE POSITION SENSOR 
    1. Disconnect the T1 TP sensor connector.
    2. Measure the resistance between the terminals of the TP sensor.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connections Throttle Valve Positions Specified Conditions
      VC (T1-2) - E2 (T1-1) - Between 2.5 k and 5.9 k
      VTA (T1-3) - E2 (T1-1) Fully closed Between 0.2 k and 5.7 k
      VTA (T1-3) - E2 (T1-1) Fully open Between 2.0 k and 10.2 k
      Fig 4: Identifying T1 TP Sensor Connector Terminals
      G04460592Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the TP sensor connector.

    NG: REPLACE THROTTLE POSITION SENSOR 

    OK: GO TO NEXT STEP 

  5. CHECK HARNESS AND CONNECTOR (ECM - THROTTLE POSITION SENSOR) 
    1. Disconnect the E3 ECM connector.
    2. Disconnect the T1 TP sensor connector.
    3. Measure the resistance.

      Standard resistance (Check for short) 

      RESISTANCE SPECIFIED CONDITIONS (FOR SHORT) (1 OF 2)

      Tester Connections Specified Conditions
      VC (T1-2) - VC (E3-18) Below 1
      VTA (T1-3) - VTA (E3-21) Below 1
      E2 (T1-1) - E2 (E3-28) Below 1

      Standard resistance (Check for short) 

      RESISTANCE SPECIFIED CONDITIONS (FOR SHORT) (2 OF 2)

      Tester Connections Specified Conditions
      VC (T1-2) or VC (E3-18) - Body ground 10 k or higher
      VTA (T1-3) or VTA (E3-28) - Body ground 10 k or higher
    4. Reconnect the TP sensor connector.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Disconnecting E3 ECM And T1 TP Sensor Connector
    G04460593Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

When Using OBD II Scan Tool: 

  1. INSPECT THROTTLE POSITION SENSOR 
    1. Disconnect the T1 Throttle Position (TP) sensor connector.
    2. Measure the resistance between the terminals of the TP sensor.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connections Throttle Valve Positions Specified Conditions
      VC (T1-2) - E2 (T1-1) - Between 2.5 k and 5.9 k
      VTA (T1-3) - E2 (T1-1) Fully closed Between 0.2 k and 5.7 k
      VTA (T1-3) - E2 (T1-1) Fully open Between 2.0 k and 10.2 k
      Fig 6: Identifying T1 Throttle Position (TP) Sensor Connector Terminals
      G04460594Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the TP sensor connector.

    NG: REPLACE THROTTLE POSITION SENSOR 

    OK: GO TO NEXT STEP 

  2. CHECK HARNESS AND CONNECTOR (THROTTLE POSITION SENSOR - ECM) 
    1. Disconnect the E3 ECM connector.
    2. Measure the resistance between the terminals of the E3 ECM connector.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connections Throttle Valve Positions Specified Conditions
      VC (T1-2) - E2 (T1-1) - Between 2.5 k and 5.9 k
      VTA (T1-3) - E2 (T1-1) Fully closed Between 0.2 k and 5.7 k
      VTA (T1-3) - E2 (T1-1) Fully open Between 2.0 k and 10.2 k
      Fig 7: Disconnecting E3 ECM Connector
      G04460595Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance.

      Standard resistance (Check for short) 

      RESISTANCE SPECIFIED CONDITIONS (FOR SHORT)

      Tester Connections Specified Conditions
      VC (E3-18) - Body ground 10 k or higher
      VTA (E3-28) - Body ground 10 k or higher
    4. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM