DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 58 (Engine Control System (A25A-FXS) - Circuit Tests (2 Of 2) & Symptom Tests) >> SFI System >> VC Output Circuit [12/2019 - ] >> Procedure

VC Output Circuit [12/2019 - ]: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK CONNECTION BETWEEN GTS AND ECM 
    1. Check the communication between the GTS 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 [12/2019 - 10/2022] , or refer to PROBLEM SYMPTOMS TABLE [10/2022 - 11/2023] , or refer to PROBLEM SYMPTOMS TABLE [11/2023 - ]

    Result: 

    A 

    See step  2

  2. CHECK EFI NO. 1 FUSE VOLTAGE 
    GTY906881Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly
    *2 EFI NO. 4 Fuse
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1 (EFI NO. 4 fuse) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      • Check the fuse with it installed to the No. 1 engine room relay block and No. 1 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 [12/2019 - 11/2023] , or refer to ECM Power Source Circuit [11/2023 - ]

    Result: 

    OK 

    See step  3

  3. CHECK CONNECTION BETWEEN GTS AND ECM (THROTTLE POSITION SENSOR) 
    1. Disconnect the throttle body with motor assembly connector.
    2. Check the communication between the GTS 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 [12/2019 - 10/2021] , or refer to INITIALIZATION [10/2021 - ]

    Result: 

    B 

    REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY 

    Refer to REMOVAL [12/2019 - 09/2020] , or refer to REMOVAL [09/2020 - ]

    Result: 

    A 

    See step  4

  4. CHECK CONNECTION BETWEEN GTS AND ECM (CRANKSHAFT POSITION SENSOR) 
    1. Disconnect the crankshaft position sensor connector.
    2. Check the communication between the GTS 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 [12/2019 - 10/2021] , or refer to REMOVAL [10/2021 - 11/2023] , or refer to REMOVAL [11/2023 - ]

    Result: 

    A 

    See step  5

  5. CHECK CONNECTION BETWEEN GTS AND ECM (CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT)) 
    1. Disconnect the camshaft position sensor (for intake camshaft) connector.
    2. Check the communication between the GTS 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) 

    Refer to PROCEDURE - Step 2

    Result: 

    A 

    See step  6

  6. CHECK CONNECTION BETWEEN GTS AND ECM (CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT)) 
    1. Disconnect the camshaft position sensor (for exhaust camshaft) connector.
    2. Check the communication between the GTS 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) 

    Refer to PROCEDURE - Step 3

    Result: 

    A 

    See step  7

  7. CHECK CONNECTION BETWEEN GTS AND ECM (MANIFOLD ABSOLUTE PRESSURE SENSOR) 
    1. Disconnect the manifold absolute pressure sensor connector.
    2. Check the communication between the GTS 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 [12/2019 - ]

    Result: 

    A 

    See step  8

  8. CHECK CONNECTION BETWEEN GTS AND ECM (OIL PRESSURE AND TEMPERATURE SENSOR) 
    1. Disconnect the oil pressure and temperature sensor connector.
    2. Check the communication between the GTS 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 OIL PRESSURE AND TEMPERATURE SENSOR 

    Refer to REMOVAL [12/2019 - ]

    Result: 

    A 

    See step  9

  9. CHECK CONNECTION BETWEEN GTS AND ECM (MASS AIR FLOW METER SUB-ASSEMBLY) 
    1. Disconnect the mass air flow meter sub-assembly connector.
    2. Check the communication between the GTS 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 [12/2019 - 10/2021] , or refer to INITIALIZATION [10/2021 - ]

    Result: 

    B 

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY 

    Refer to REMOVAL [12/2019 - ]

    Result: 

    A 

    See step  10

  10. CHECK CONNECTION BETWEEN GTS AND ECM (FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE)) 
    1. Disconnect the fuel pressure sensor (for high pressure side) connector.
    2. Check the communication between the GTS 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 [12/2019 - 10/2021] , or refer to INITIALIZATION [10/2021 - ]

    Result: 

    B 

    REPLACE FUEL PRESSURE SENSOR (FOR HIGH PRESSURE SIDE) 

    Refer to REMOVAL [12/2019 - 10/2021] , or refer to REMOVAL [10/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

    Result: 

    A 

    See step  11

  11. CHECK CONNECTION BETWEEN GTS 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. Check the communication between the GTS 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 [12/2019 - 10/2021] , or refer to INITIALIZATION [10/2021 - ]

    Result: 

    B 

    REPLACE NO. 2 FUEL PRESSURE SENSOR (FOR LOW PRESSURE SIDE) 

    Refer to REMOVAL [12/2019 - 10/2021] , or refer to REMOVAL [10/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

    Result: 

    A 

    See step  12

  12. CHECK CONNECTION BETWEEN GTS AND ECM (FUEL TANK PRESSURE SENSOR) 
    1. Disconnect the fuel tank pressure sensor connector.
    2. Check the communication between the GTS 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 [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

    Result: 

    A 

    See step  13

  13. CHECK CONNECTION BETWEEN GTS AND ECM (CANISTER PUMP MODULE) 
    1. Disconnect the canister pump module connector.
    2. Check the communication between the GTS 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 [12/2019 - ]

    Result: 

    A 

    See step  14

  14. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the throttle body with motor assembly connector.
    2. Disconnect the crankshaft position sensor connector.
    3. Disconnect the camshaft position sensor (for intake camshaft) connector.
    4. Disconnect the camshaft position sensor (for exhaust camshaft) connector.
    5. Disconnect the manifold absolute pressure sensor connector.
    6. Disconnect the oil pressure and temperature sensor connector.
    7. Disconnect the mass air flow meter sub-assembly connector.
    8. Disconnect the fuel pressure sensor (for high pressure side) connector.
    9. Disconnect the No. 2 fuel pressure sensor (for low pressure side) connector.
    10. Disconnect the fuel tank pressure sensor connector.
    11. Disconnect the canister pump module connector.
    12. Disconnect the ECM connectors.
    13. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C55-109 (VCTA) - Body ground Always 10 kΩ or higher
      C55-116 (VCNE) - Body ground Always 10 kΩ or higher
      C55-88 (VCV1) - Body ground Always 10 kΩ or higher
      C55-113 (VCE1) - Body ground Always 10 kΩ or higher
      C55-121 (VCPM) - Body ground Always 10 kΩ or higher
      C55-99 (VCPE) - Body ground Always 10 kΩ or higher
      C55-78 (VCVG) - Body ground Always 10 kΩ or higher
      C55-98 (VCPR) - Body ground Always 10 kΩ or higher
      C55-84 (VCPF) - Body ground Always 10 kΩ or higher
      A27-57 (VPTK) - Body ground Always 10 kΩ or higher
      A27-48 (VCPP) - Body ground Always 10 kΩ or higher
    14. Remove the VVT, EFI-MAIN NO. 2 and EFI-MAIN NO. 3 relays from the No. 1 engine room relay block and No. 1 junction block assembly.

      HINT: 

      Remove the VVT, EFI-MAIN NO. 2 and EFI-MAIN NO. 3 relays connected between the checked terminals as the coil inside the relay influences the measurement value.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A27-9 (+B) - 1 (EFI NO. 4 fuse) Always Below 1 Ω
      A27-35 (+B2) - 1 (EFI NO. 4 fuse) Always Below 1 Ω
      A27-9 (+B) - Body ground Always 10 kΩ or higher
      A27-35 (+B2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM 

    Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

Diesel-Data.com