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VC Output Circuit [09/2015 - ]: Procedure

  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG) and Techstream on.
    3. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    (Refer to PROBLEM SYMPTOMS TABLE [09/2015 - ] )

    Result: 

    A 

    See step  2

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ECM) 
    1. Turn the engine switch on (IG).
      GTY565398Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1 (EFI No. 2 fuse) - Body ground Engine switch on (IG) 11 to 14 V
      TEXT ILLUSTRATION

      *1 Engine Room Relay Block
      *2 EFI No. 2 Fuse

      HINT: 

      If the result is not as specified, since current is not flowing to the +B and +B2 terminals of the ECM, the system may not be started.

    Result: 

    NG 

    GO TO ECM POWER SOURCE CIRCUIT 

    (Refer to ECM Power Source Circuit [09/2015 - ] )

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (THROTTLE POSITION SENSOR) 
    1. Disconnect the throttle body connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

      HINT: 

      Perform "Inspection After Repair" after replacing the throttle body assembly (Refer to INITIALIZATION [09/2015 - ] ).

    Result: 

    B 

    REPLACE THROTTLE BODY ASSEMBLY 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  4

  4. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the accelerator pedal position sensor connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  5

  5. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CANISTER PUMP MODULE) 
    1. Disconnect the canister pump module connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE CANISTER ASSEMBLY 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  6

  6. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (AIR SWITCHING VALVE for Bank 1) 
    1. Disconnect the air switching valve (for Bank 1) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE AIR SWITCHING VALVE ASSEMBLY 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  7

  7. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (AIR SWITCHING VALVE for Bank 2) 
    1. Disconnect the air switching valve (for Bank 2) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE AIR SWITCHING VALVE ASSEMBLY 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  8

  8. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (POWER STEERING OIL PRESSURE SENSOR) 
    1. Disconnect the power steering oil pressure sensor connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE POWER STEERING OIL PRESSURE SENSOR 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  9

  9. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR) 
    1. Disconnect the camshaft position sensor connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE CAMSHAFT POSITION SENSOR 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  10

  10. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CRANKSHAFT POSITION SENSOR) 
    1. Disconnect the crankshaft position sensor connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE CRANKSHAFT POSITION SENSOR 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  11

  11. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR for Intake Side of Bank 1) 
    1. Disconnect the VVT sensor (for Intake Side of Bank 1) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE VVT SENSOR (for Intake Side of Bank 1) 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  12

  12. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR for Exhaust Side of Bank 1) 
    1. Disconnect the VVT sensor (for Exhaust Side of Bank 1) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE VVT SENSOR (for Exhaust Side of Bank 1) 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  13

  13. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR for Intake Side of Bank 2) 
    1. Disconnect the VVT sensor (for Intake Side of Bank 2) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE VVT SENSOR (for Intake Side of Bank 2) 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  14

  14. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR for Exhaust Side of Bank 2) 
    1. Disconnect the VVT sensor (for Exhaust Side of Bank 2) connector.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Check the communication between the Techstream and ECM.

      HINT: 

      It can be checked using the "Engine" item of the Data List.

      RESULT

      Result Proceed to
      Communication is not possible A
      Communication is possible B

    Result: 

    B 

    REPLACE VVT SENSOR (for Exhaust Side of Bank 2) 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    A 

    See step  15

  15. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the throttle body connector.
    2. Disconnect the accelerator pedal position sensor connector.
    3. Disconnect the canister pump module connector.
    4. Disconnect the air switching valve (for Bank 1) connector.
    5. Disconnect the air switching valve (for Bank 2) connector.
    6. Disconnect the power steering oil pressure sensor connector.
    7. Disconnect the camshaft position sensor connector.
    8. Disconnect the crankshaft position sensor connector.
    9. Disconnect the VVT sensor (for Intake Side of Bank 1) connector.
    10. Disconnect the VVT sensor (for Exhaust Side of Bank 1) connector.
    11. Disconnect the VVT sensor (for Intake Side of Bank 2) connector.
    12. Disconnect the VVT sensor (for Exhaust Side of Bank 2) connector.
    13. Disconnect the ECM connectors.
    14. Disconnect the No. 1 integration relay connectors.
    15. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C53-125 (VCTA) - Body ground Always 10 kΩ or higher
      A38-55 (VCPA) - Body ground Always 10 kΩ or higher
      A38-58 (VCP2) - Body ground Always 10 kΩ or higher
      C53-102 (VCPP) - Body ground Always 10 kΩ or higher
      C53-75 (VCAI) - Body ground Always 10 kΩ or higher
      C53-87 (VCV1) - Body ground Always 10 kΩ or higher
      C53-110 (VCV2) - Body ground Always 10 kΩ or higher
      C53-64 (VCNE) - Body ground Always 10 kΩ or higher
    16. Remove the F/PMP relay, integration relay (A/F relay) from the engine room relay block.

      HINT: 

      Remove the F/PMP relay, integration relay (A/F relay) connected between the checked terminals as the coil inside the relay influences the measurement value.

    17. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      1Q-11 or A38-2 (+B) - Body ground Always 10 kΩ or higher
      1Q-11 or A38-3 (+B2) - Body ground Always 10 kΩ or higher
      1Q-11 - A38-2 (+B) Always Below 1 Ω
      1Q-11 - A38-3 (+B2) Always Below 1 Ω

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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