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VC Output Circuit [01/2017 - ]: Procedure

  1. CHECK CONNECTION 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" 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 [01/2017 - ] 

    Result: 

    A 

    See step  2

  2. CHECK EFI NO. 1 FUSE VOLTAGE 
    1. Turn the power switch on (IG).
      GTY806498Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 No. 1 Engine Room Relay Block and Junction Block Assembly
      *2 EFI NO. 1 Fuse
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1 (EFI NO. 1 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: 

    NG 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [01/2017 - ]  

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTION 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" 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 [01/2017 - 09/2018] , or refer to INITIALIZATION [09/2018 - 04/2020] , or refer to INITIALIZATION [04/2020 - ]

    Result: 

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY. Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  4

  4. CHECK CONNECTION 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" 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 CAMSHAFT OF BANK 1). Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  5

  5. CHECK CONNECTION 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" 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 CAMSHAFT OF BANK 2). Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  6

  6. CHECK CONNECTION 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" 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 CAMSHAFT OF BANK 1). Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  7

  7. CHECK CONNECTION 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" 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 CAMSHAFT OF BANK 2). Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  8

  8. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CRANKSHAFT POSITION SENSOR) 
    1. Disconnect the crankshaft position 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" 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 [01/2017 - ] 

    Result: 

    A 

    See step  9

  9. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE)) 
    1. Disconnect the fuel pressure sensor (for high pressure side) 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" 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 (for high pressure side).

      Refer to INITIALIZATION [01/2017 - 09/2018] , or refer to INITIALIZATION [09/2018 - 04/2020] , or refer to INITIALIZATION [04/2020 - ]

    Result: 

    B 

    REPLACE FUEL DELIVERY PIPE WITH SENSOR ASSEMBLY LH (FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE)). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    A 

    See step  10

  10. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the fuel pressure sensor (for low pressure side) 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" 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 (for low pressure side).

      Refer to INITIALIZATION [01/2017 - 09/2018] , or refer to INITIALIZATION [09/2018 - 04/2020] , or refer to INITIALIZATION [04/2020 - ]

    Result: 

    B 

    REPLACE FUEL DELIVERY PIPE WITH SENSOR ASSEMBLY (FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE)). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    A 

    See step  11

  11. CHECK CONNECTION 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" item of the Data List.

      Result

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

    Result: 

    B 

    REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR. Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  12

  12. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (MASS AIR FLOW METER SUB-ASSEMBLY) 
    1. Disconnect the mass air flow meter sub-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" 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 mass air flow meter sub-assembly.

      Refer to INITIALIZATION [01/2017 - 09/2018] , or refer to INITIALIZATION [09/2018 - 04/2020] , or refer to INITIALIZATION [04/2020 - ]

    Result: 

    B 

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY. Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  13

  13. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (FUEL TANK PRESSURE SENSOR) 
    1. Disconnect the fuel tank 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" item of the Data List.

      Result

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

    Result: 

    B 

    REPLACE FUEL TANK PRESSURE SENSOR. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    A 

    See step  14

  14. CHECK CONNECTION 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" item of the Data List.

      Result

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

    Result: 

    B 

    REPLACE CANISTER PUMP MODULE. Refer to  REMOVAL [01/2017 - ] 

    Result: 

    A 

    See step  15

  15. 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 crankshaft position sensor connector.
    7. Disconnect the fuel pressure sensor (for high pressure side) connector.
    8. Disconnect the fuel pressure sensor (for low pressure side) connector.
    9. Disconnect the manifold absolute pressure sensor connector.
    10. Disconnect the mass air flow meter sub-assembly connector.
    11. Disconnect the canister pump module connector.
    12. Disconnect the fuel tank pressure sensor connector.
    13. Disconnect the ECM connectors.
    14. Remove the A/F HTR relay from the No. 1 engine room relay block and junction block assembly.
    15. Remove the EFI-MAIN NO. 2 relay from the No. 2 luggage room relay block and junction block assembly.

      HINT: 

      Remove the EFI-MAIN No. 2 relay and A/F HTR relay connected between the checked terminals as the coil inside the relay influences the measurement value.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      G1-121 (VCTA) - Body ground Always 10 kΩ or higher
      G1-99 (VCV1) - Body ground Always 10 kΩ or higher
      G1-98 (VCV2) - Body ground Always 10 kΩ or higher
      G1-140 (VCE1) - Body ground Always 10 kΩ or higher
      G1-139 (VCE2) - Body ground Always 10 kΩ or higher
      G1-96 (VCNE) - Body ground Always 10 kΩ or higher
      G1-119 (VCPR) - Body ground Always 10 kΩ or higher
      G1-111 (VCPF) - Body ground Always 10 kΩ or higher
      G1-77 (VCPM) - Body ground Always 10 kΩ or higher
      G1-90 (VCVG) - Body ground Always 10 kΩ or higher
      A58-56 (VPTK) - Body ground Always 10 kΩ or higher
      A58-35 (VCPP) - Body ground Always 10 kΩ or higher
      A58-2 (+B) - 1 (EFI NO. 1 fuse) Always Below 1 Ω
      A58-3 (+B2) - 1 (EFI NO. 1 fuse) Always Below 1 Ω
      A58-2 (+B) - Body ground Always 10 kΩ or higher
      A58-3 (+B2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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