ECD SYSTEM(w/ DPF) VC Output Circuit

DESCRIPTION

The ECM constantly generates 5 V of power from the battery voltage supplied to the +B (BATT) terminal to operate the microprocessor. The ECM also provides this power to the sensors through the VC output circuit.

B0018GME50

When the VC circuit has a short circuit, the CPU in the ECM and sensors that are supplied power through the VC circuit are deactivated because power is not supplied from the VC circuit. When the system is in this condition, it will not start.

Tech Tips

Under normal conditions, the MIL is illuminated for several seconds when the engine switch is first turned on (IG). The MIL goes off when the engine is started.

WIRING DIAGRAM


A01WV7SE01
A01WSNAE01
A01WQTVE01

CAUTION / NOTICE / HINT

Note


  • Check the fuses for circuits related to this system before performing the following inspection procedure.

  • After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.

PROCEDURE


  1. CHECK COMMUNICATION BETWEEN GTS AND ECM


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and GTS on.

    3. Check the communication between the GTS and ECM.

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

    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    A

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ECM)


    1. A01WUHGE04
      Text Illustration
      *1 Engine Room Relay Block
      *2 EFI No. 2 Fuse

      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 No. 2 fuse) - Body ground Engine switch on (IG) 11 to 14 V

      Tech Tips

      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.


    NG

    GO TO ECM POWER SOURCE CIRCUIT

    OK

  3. CHECK CONNECTION BETWEEN GTS AND ECM (THROTTLE POSITION SENSOR (for Bank 1))


    1. Disconnect the throttle position sensor (for Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the throttle position sensor (for Bank 1) connector.


    A

    REPLACE DIESEL THROTTLE BODY ASSEMBLY (for Bank 1) Click here

    B

  4. CHECK CONNECTION BETWEEN GTS AND ECM (THROTTLE POSITION SENSOR (for Bank 2))


    1. Disconnect the throttle position sensor (for Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the throttle position sensor (for Bank 2) connector.


    A

    REPLACE DIESEL THROTTLE BODY ASSEMBLY (for Bank 2) Click here

    B

  5. CHECK CONNECTION BETWEEN GTS AND ECM (NO. 1 EGR VALVE POSITION SENSOR)


    1. Disconnect the No. 1 EGR valve connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the No. 1 EGR valve connector.


    A

    REPLACE NO. 1 EGR VALVE ASSEMBLY Click here

    B

  6. CHECK CONNECTION BETWEEN GTS AND ECM (NO. 2 EGR VALVE POSITION SENSOR)


    1. Disconnect the No. 2 EGR valve connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the No. 2 EGR valve connector.


    A

    REPLACE NO. 2 EGR VALVE ASSEMBLY Click here

    B

  7. CHECK CONNECTION BETWEEN GTS AND ECM (ACCELERATOR PEDAL POSITION SENSOR)


    1. Disconnect the accelerator pedal position sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the accelerator pedal position sensor connector.


    A

    REPLACE ACCELERATOR PEDAL ROD ASSEMBLY Click here

    B

  8. CHECK CONNECTION BETWEEN GTS AND ECM (MANIFOLD ABSOLUTE PRESSURE SENSOR)


    1. Disconnect the manifold absolute pressure sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the manifold absolute pressure sensor connector.


    A

    REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR Click here

    B

  9. CHECK CONNECTION BETWEEN GTS AND ECM (FUEL PRESSURE SENSOR)


    1. Disconnect the fuel pressure sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the fuel pressure sensor connector.


    A

    REPLACE COMMON RAIL (for Bank 1) Click here

    B

  10. CHECK CONNECTION BETWEEN GTS AND ECM (DIFFERENTIAL PRESSURE SENSOR ASSEMBLY (for Bank 1))


    1. Disconnect the differential pressure sensor assembly (for Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the differential pressure sensor assembly (for Bank 1) connector.


    A

    REPLACE DIFFERENTIAL PRESSURE SENSOR (for Bank 1) Click here

    B

  11. CHECK CONNECTION BETWEEN GTS AND ECM (DIFFERENTIAL PRESSURE SENSOR ASSEMBLY (for Bank 2))


    1. Disconnect the differential pressure sensor assembly (for Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the differential pressure sensor assembly (for Bank 2) connector.


    A

    REPLACE DIFFERENTIAL PRESSURE SENSOR (for Bank 2) Click here

    B

  12. CHECK CONNECTION BETWEEN GTS AND ECM (NOZZLE VANE POSITION SENSOR (for Bank 1))


    1. Disconnect the nozzle vane position sensor (for Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the nozzle vane position sensor (for Bank 1) connector.


    A

    REPLACE TURBOCHARGER SUB-ASSEMBLY (for Bank 1) Click here

    B

  13. CHECK CONNECTION BETWEEN GTS AND ECM (NOZZLE VANE POSITION SENSOR (for Bank 2))


    1. Disconnect the nozzle vane position sensor (for Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the nozzle vane position sensor (for Bank 2) connector.


    A

    REPLACE TURBOCHARGER SUB-ASSEMBLY (for Bank 2) Click here

    B

  14. CHECK HARNESS AND CONNECTOR


    1. Disconnect the throttle position sensor (for Bank 1) connector.

    2. Disconnect the throttle position sensor (for Bank 2) connector.

    3. Disconnect the No. 1 EGR valve connector.

    4. Disconnect the No. 2 EGR valve connector.

    5. Disconnect the accelerator pedal position sensor connector.

    6. Disconnect the manifold absolute pressure sensor connector.

    7. Disconnect the fuel pressure sensor connector.

    8. Disconnect the differential pressure sensor assembly (for Bank 1) connector.

    9. Disconnect the differential pressure sensor assembly (for Bank 2) connector.

    10. Disconnect the nozzle vane position sensor (for Bank 1) connector.

    11. Disconnect the nozzle vane position sensor (for Bank 2) connector.

    12. Disconnect the ECM connectors.

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

      Standard Resistance (Check for Short)
      for LHD
      Tester Connection Condition Specified Condition
      C110-91 (VC) - Body ground Always 10 kΩ or higher
      C110-110 (VCVL) - Body ground Always 10 kΩ or higher
      C110-118 (VCM) - Body ground Always 10 kΩ or higher
      C110-120 (VNVC) - Body ground Always 10 kΩ or higher
      C110-66 (VCPM) - Body ground Always 10 kΩ or higher
      A85-55 (VCPA) - Body ground Always 10 kΩ or higher
      A85-56 (VCP2) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      C138-91 (VC) - Body ground Always 10 kΩ or higher
      C138-110 (VCVL) - Body ground Always 10 kΩ or higher
      C138-118 (VCM) - Body ground Always 10 kΩ or higher
      C138-120 (VNVC) - Body ground Always 10 kΩ or higher
      C138-66 (VCPM) - Body ground Always 10 kΩ or higher
      A86-55 (VCPA) - Body ground Always 10 kΩ or higher
      A86-56 (VCP2) - Body ground Always 10 kΩ or higher

    14. Reconnect the throttle position sensor (for Bank 1) connector.

    15. Reconnect the throttle position sensor (for Bank 2) connector.

    16. Reconnect the No. 1 EGR valve connector.

    17. Reconnect the No. 2 EGR valve connector.

    18. Reconnect the accelerator pedal position sensor connector.

    19. Reconnect the manifold absolute pressure sensor connector.

    20. Reconnect the fuel pressure sensor connector.

    21. Reconnect the differential pressure sensor assembly (for Bank 1) connector.

    22. Reconnect the differential pressure sensor assembly (for Bank 2) connector.

    23. Reconnect the nozzle vane position sensor (for Bank 1) connector.

    24. Reconnect the nozzle vane position sensor (for Bank 2) connector.

    25. Reconnect the ECM connectors.


    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR