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VC Output Circuit [12/2017 - 10/2020]: Procedure

  1. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM 
    1. Connect the Techstream to the DLC3.
    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 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [12/2017 - ] 

    Result: 

    A 

    See step  2

  2. CHECK EFI-B NO. 1 FUSE VOLTAGE 
    GTY821123Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 EFI-B NO. 1 Fuse
    1. Turn the engine 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-B NO. 1 fuse) - Body ground Engine 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 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 [12/2017 - 10/2020] 

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (THROTTLE POSITION SENSOR (BANK 1)) 
    1. Disconnect the throttle body with motor assembly (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

      HINT: 

      • When cleaning or replacing one throttle body with motor assembly, clean the other throttle body with motor assembly.

        Refer to PROCEDURE - Step 4

      • Perform "Inspection After Repair" after replacing the throttle body with motor assembly.

        Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY (BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  4

  4. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (THROTTLE POSITION SENSOR (BANK 2)) 
    1. Disconnect the throttle body with motor assembly (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

      HINT: 

      • When cleaning or replacing one throttle body with motor assembly, clean the other throttle body with motor assembly.

        Refer to PROCEDURE - Step 4

      • Perform "Inspection After Repair" after replacing the throttle body with motor assembly.

        Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY (BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  5

  5. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT OF BANK 1)) 
    1. Disconnect the camshaft position sensor (for intake camshaft 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 CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT OF BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  6

  6. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT OF BANK 2)) 
    1. Disconnect the camshaft position sensor (for intake camshaft 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 CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT OF BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  7

  7. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1)) 
    1. Disconnect the camshaft position sensor (for exhaust camshaft 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 CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  8

  8. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2)) 
    1. Disconnect the camshaft position sensor (for exhaust camshaft 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 CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  9

  9. CHECK COMMUNICATION 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 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 fuel pressure sensor (for high pressure side).

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE). Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020] 

    Result: 

    A 

    See step  10

  10. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 2 FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the No. 2 fuel pressure sensor (for low pressure side) 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 No. 2 fuel pressure sensor (for low pressure side).

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE NO. 2 FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020] 

    Result: 

    A 

    See step  11

  11. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 2 TURBO PRESSURE SENSOR (BANK 1)) 
    1. Disconnect the No. 2 turbo pressure sensor (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 NO. 2 TURBO PRESSURE SENSOR (BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  12

  12. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 2 TURBO PRESSURE SENSOR (BANK 2)) 
    1. Disconnect the No. 2 turbo pressure sensor (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 NO. 2 TURBO PRESSURE SENSOR (BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  13

  13. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VACUUM SENSOR ASSEMBLY (BANK 1)) 
    1. Disconnect the vacuum sensor assembly (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 VACUUM SENSOR ASSEMBLY (BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  14

  14. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (VACUUM SENSOR ASSEMBLY (BANK 2)) 
    1. Disconnect the vacuum sensor assembly (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 VACUUM SENSOR ASSEMBLY (BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  15

  15. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 1 TURBO PRESSURE SENSOR (BANK 1)) 
    1. Disconnect the No. 1 turbo pressure sensor (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 NO. 1 TURBO PRESSURE SENSOR (BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  16

  16. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 1 TURBO PRESSURE SENSOR (BANK 2)) 
    1. Disconnect the No. 1 turbo pressure sensor (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 NO. 1 TURBO PRESSURE SENSOR (BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  17

  17. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (WASTE GATE VALVE POSITION SENSOR (BANK 1)) 
    1. Disconnect the waste gate valve actuator assembly (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

      HINT: 

      Perform "Inspection After Repair" after replacing the turbocharger sub-assembly.

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE WASTE GATE VALVE ACTUATOR ASSEMBLY (TURBOCHARGER SUB-ASSEMBLY) (BANK 1). Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - ] 

    Result: 

    A 

    See step  18

  18. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (WASTE GATE VALVE POSITION SENSOR (BANK 2)) 
    1. Disconnect the waste gate valve actuator assembly (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

      HINT: 

      Perform "Inspection After Repair" after replacing the turbocharger sub-assembly.

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE WASTE GATE VALVE ACTUATOR ASSEMBLY (TURBOCHARGER SUB-ASSEMBLY) (BANK 2). Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - ] 

    Result: 

    A 

    See step  19

  19. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (BALL VALVE POSITION SENSOR) 
    1. Disconnect the water control valve 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 WATER CONTROL VALVE. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020] 

    Result: 

    A 

    See step  20

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

      HINT: 

      Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY (BANK 1). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  21

  21. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (MASS AIR FLOW METER SUB-ASSEMBLY (BANK 2)) 
    1. Disconnect the mass air flow meter sub-assembly (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

      HINT: 

      Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

      Refer to INITIALIZATION [12/2017 - 10/2020]

    Result: 

    B 

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY (BANK 2). Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  22

  22. CHECK COMMUNICATION 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 [12/2017 - ] 

    Result: 

    A 

    See step  23

  23. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (ACCELERATOR PEDAL POSITION SENSOR) 
    1. Disconnect the accelerator pedal sensor assembly 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 [12/2017 - ] 

    Result: 

    A 

    See step  24

  24. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM (NO. 3 TURBO PRESSURE SENSOR) 
    1. Disconnect the No. 3 turbo 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 NO. 3 TURBO PRESSURE SENSOR. Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  25

  25. CHECK COMMUNICATION 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 PUMP MODULE. Refer to  REMOVAL [12/2017 - ] 

    Result: 

    A 

    See step  26

  26. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the throttle body with motor assembly (bank 1) connector.
    2. Disconnect the throttle body with motor assembly (bank 2) connector.
    3. Disconnect the camshaft position sensor (for intake camshaft of bank 1) connector.
    4. Disconnect the camshaft position sensor (for intake camshaft of bank 2) connector.
    5. Disconnect the camshaft position sensor (for exhaust camshaft of bank 1) connector.
    6. Disconnect the camshaft position sensor (for exhaust camshaft of bank 2) 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 vacuum sensor assembly (bank 1) connector.
    10. Disconnect the vacuum sensor assembly (bank 2) connector.
    11. Disconnect the No. 1 turbo pressure sensor (bank 1) connector.
    12. Disconnect the No. 1 turbo pressure sensor (bank 2) connector.
    13. Disconnect the No. 2 turbo pressure sensor (bank 1) connector.
    14. Disconnect the No. 2 turbo pressure sensor (bank 2) connector.
    15. Disconnect the waste gate valve actuator assembly (bank 1) connector.
    16. Disconnect the waste gate valve actuator assembly (bank 2) connector.
    17. Disconnect the water control valve connector.
    18. Disconnect the mass air flow meter sub-assembly (bank 1) connector.
    19. Disconnect the mass air flow meter sub-assembly (bank 2) connector.
    20. Disconnect the crankshaft position sensor connector.
    21. Disconnect the accelerator pedal sensor assembly connector.
    22. Disconnect the No. 3 turbo pressure sensor connector.
    23. Disconnect the canister pump module connector.
    24. Disconnect the ECM connectors.
    25. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D1-129 (VCTA) - Body ground Always 10 kΩ or higher
      D1-117 (VCT2) - Body ground Always 10 kΩ or higher
      D1-94 (VCV1) - Body ground Always 10 kΩ or higher
      D1-96 (VCPR) - Body ground Always 10 kΩ or higher
      D1-106 (VCWG) - Body ground Always 10 kΩ or higher
      D1-107 (VCVG) - Body ground Always 10 kΩ or higher
      D1-95 (VCNE) - Body ground Always 10 kΩ or higher
      A95-57 (VCPA) - Body ground Always 10 kΩ or higher
      A95-60 (VCP2) - Body ground Always 10 kΩ or higher
      D1-127 (VCPM) - Body ground Always 10 kΩ or higher
      A95-48 (VCPP) - Body ground Always 10 kΩ or higher
      5 (EFI-MAIN NO. 1 relay) - D2-12 (+B) Always Below 1 Ω
      5 (EFI-MAIN NO. 1 relay) - D2-11 (+B2) Always Below 1 Ω
      5 (EFI-MAIN NO. 1 relay) - D2-10 (+B3) Always Below 1 Ω
      5 (EFI-MAIN NO. 1 relay) - D2-9 (+B4) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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