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VC Output Circuit [10/2015 - ]: Procedure

  1. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  3

    B 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2015 - ] 

    Result:  1

    A 

    See step  2

  2. CHECK EFI NO. 2 FUSE VOLTAGE 
    GTY536462Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 EFI NO. 2 Fuse
    1. Turn the power switch on (IG).
    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 Power switch on (IG) 11 to 14 V

      HINT: 

      • Check the fuse with it installed to the No. 1 engine room relay block and junction block assembly.
      • 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

      Proceed to
      OK
      NG

    Result:  2

    NG 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [09/2014 - ]  

    Result:  1

    OK 

    See step  3

  3. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (THROTTLE POSITION SENSOR) 
    1. Disconnect the throttle body with motor assembly connector.
    2. Turn the power 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 and ECT" 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 with motor assembly.

      Refer to INITIALIZATION [09/2014 - ]

    Result:  2

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  4

  4. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 1) 
    1. Disconnect the VVT sensor (for intake camshaft of bank 1) connector.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  2

    B 

    REPLACE VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 1). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  5

  5. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 2) 
    1. Disconnect the VVT sensor (for intake camshaft of bank 2) connector.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  2

    B 

    REPLACE VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 2). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  6

  6. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1) 
    1. Disconnect the VVT sensor (for exhaust camshaft of bank 1) connector.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  2

    B 

    REPLACE CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  7

  7. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2) 
    1. Disconnect the VVT sensor (for exhaust camshaft of bank 2) connector.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  2

    B 

    REPLACE CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  8

  8. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (FUEL PRESSURE SENSOR) 
    1. Disconnect the fuel pressure sensor connector.
    2. Turn the power 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 and ECT" 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 fuel pressure sensor.

      Refer to INITIALIZATION [09/2014 - ]

    Result:  2

    B 

    REPLACE FUEL DELIVERY PIPE SUB-ASSEMBLY (FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  9

  9. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (MANIFOLD ABSOLUTE PRESSURE SENSOR) 
    1. Disconnect the manifold absolute pressure sensor connector.
    2. Turn the power 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 and ECT" 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 manifold absolute pressure sensor.

      Refer to INITIALIZATION [09/2014 - ]

    Result:  2

    B 

    REPLACE FUEL DELIVERY PIPE (FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  10

  10. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (CANISTER PUMP MODULE) 
    1. Disconnect the canister pump module connector.
    2. Turn the power 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 and ECT" item of the Data List.

      Result

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

    Result:  2

    B 

    REPLACE CANISTER PUMP MODULE. Refer to  REMOVAL [09/2014 - ] 

    Result:  1

    A 

    See step  11

  11. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the throttle body with motor assembly connector.
    2. Disconnect the VVT sensor (for intake camshaft of bank 1) connector.
    3. Disconnect the VVT sensor (for intake camshaft of bank 2) connector.
    4. Disconnect the VVT sensor (for exhaust camshaft of bank 1) connector.
    5. Disconnect the VVT sensor (for exhaust camshaft of bank 2) connector.
    6. Disconnect the fuel pressure sensor connector.
    7. Disconnect the manifold absolute pressure sensor connector.
    8. Disconnect the canister pump module connector.
    9. Disconnect the ECM connectors.
    10. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F5-126 (VCTA) - Body ground and other terminals Always 10 kΩ or higher
      F5-88 (VCPR) - Body ground and other terminals Always 10 kΩ or higher
      F5-89 (VCE1) - Body ground and other terminals Always 10 kΩ or higher
      F5-90 (VCE2) - Body ground and other terminals Always 10 kΩ or higher
      F5-82 (VCV1) - Body ground and other terminals Always 10 kΩ or higher
      F5-111 (VCV2) - Body ground and other terminals Always 10 kΩ or higher
      A20-35 (VC) - Body ground and other terminals Always 10 kΩ or higher
      F5-94 (VCPM) - Body ground and other terminals Always 10 kΩ or higher
      A20-2 (+B) - 1 (EFI NO. 2 fuse) Always Below 1 Ω
      A20-3 (+B2) - 1 (EFI NO. 2 fuse) Always Below 1 Ω
      A20-2 (+B) - Body ground and other terminals Always 10 kΩ or higher
      A20-3 (+B2) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE ECM. Refer to  REMOVAL [09/2014 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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