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VC Output Circuit [10/2015 - ]: Procedure

  1. READ VALUE USING TECHSTREAM 
    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 [10/2015 - 05/2018]  , or refer to  PROBLEM SYMPTOMS TABLE [05/2018 - ] 

    Result: 

    A 

    See step  2

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ECM) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value (s) in the table below.
      GTY611911Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (ECM)

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A12-7 (+B) - E3-1 (E1) Engine switch on (IG) 11 to 14 V
      A12-6 (+B2) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

      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

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [10/2015 - ]  

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (THROTTLE POSITION SENSOR) 
    1. Disconnect the E36 throttle body with motor 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

      HINT: 

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

      Refer to INITIALIZATION [10/2015 - ]

    Result: 

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    A 

    See step  4

  4. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (ACCELERATOR PEDAL SENSOR) 
    1. Disconnect the A1 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 [10/2015 - ] 

    Result: 

    A 

    See step  5

  5. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (MASS AIR FLOW METER) 
    1. Disconnect the E38 mass air flow meter 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.

      Refer to INITIALIZATION [10/2015 - ]

    Result: 

    B 

    REPLACE MASS AIR FLOW METER. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    A 

    See step  6

  6. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (FUEL DELIVERY PIPE LH (FUEL PRESSURE SENSOR)) 
    1. Disconnect the H17 fuel delivery pipe LH (fuel pressure sensor).
    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 FUEL DELIVERY PIPE SUB-ASSEMBLY (FUEL PRESSURE SENSOR). Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  7

  7. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 1)) 
    1. Disconnect the E21 VVT 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 VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 1). Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  8

  8. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 2)) 
    1. Disconnect the E27 VVT 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 VVT SENSOR (FOR INTAKE CAMSHAFT OF BANK 2). Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  9

  9. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1)) 
    1. Disconnect the E16 VVT 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 VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 1). Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  10

  10. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2)) 
    1. Disconnect the E29 VVT 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 VVT SENSOR (FOR EXHAUST CAMSHAFT OF BANK 2). Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  11

  11. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CAMSHAFT POSITION SENSOR) 
    1. Disconnect the E37 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 [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    A 

    See step  12

  12. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CRANKSHAFT POSITION SENSOR) 
    1. Disconnect the c1 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 [10/2015 - ] 

    Result: 

    A 

    See step  13

  13. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM (CANISTER PUMP MODULE) 
    1. Disconnect the U34 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 [10/2015 - ] 

    Result: 

    A 

    See step  14

  14. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the E36 throttle body with motor assembly connector.
    2. Disconnect the A1 accelerator pedal sensor assembly connector.
    3. Disconnect the E38 mass air flow meter connector.
    4. Disconnect the H17 fuel delivery pipe LH (fuel pressure sensor).
    5. Disconnect the E21 VVT sensor (for intake camshaft of bank 1) connector.
    6. Disconnect the E27 VVT sensor (for intake camshaft of bank 2) connector.
    7. Disconnect the E16 VVT sensor (for exhaust camshaft of bank 1) connector.
    8. Disconnect the E29 VVT sensor (for exhaust camshaft of bank 2) connector.
    9. Disconnect the E37 camshaft position sensor connector.
    10. Disconnect the c1 crankshaft position sensor connector.
    11. Disconnect the U34 canister pump module connector.
    12. Disconnect the E2, A12, E1 and E4 ECM connectors.
    13. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E2-26 (VC) - Body ground and other terminals Always 10 kΩ or higher
      E2-34 (VCTA) - Body ground and other terminals Always 10 kΩ or higher
      A12-20 (VCPA) - Body ground and other terminals Always 10 kΩ or higher
      A12-22 (VCP2) - Body ground and other terminals Always 10 kΩ or higher
      E1-21 (VCVG) - Body ground and other terminals Always 10 kΩ or higher
      E4-28 (VCPR) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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