ECD SYSTEM VC Output Circuit

DTC Code DTC Name
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.

A275101E02

When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that are supplied with power through the VC circuit are deactivated because the power is not supplied from the VC circuit. Under this condition, the system does not start up and the MIL does not illuminate even if the system malfunctions.

Tip:

Under normal conditions, the MIL is illuminated when the ignition switch is turned ON. The MIL goes off when the engine is started.

WIRING DIAGRAM

A299057E02
A299058E02
A299059E02

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. CHECK MIL

    1. Check that the Malfunction Indicator Lamp (MIL) illuminates when turning the ignition switch to ON.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    A

  2. CHECK COMMUNICATION BETWEEN GTS AND ECM

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON 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

    GO TO MIL CIRCUIT

    Click hereClick here

    A

  3. CHECK MIL (ACCELERATOR PEDAL SENSOR ASSEMBLY)

    1. Disconnect the accelerator pedal sensor assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY

    Click here

    A

  4. CHECK MIL (DIESEL THROTTLE BODY ASSEMBLY)

    1. Disconnect the diesel throttle body assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE DIESEL THROTTLE BODY ASSEMBLY

    Click here

    A

  5. CHECK MIL (FUEL PRESSURE SENSOR)

    1. Disconnect the fuel pressure sensor connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE COMMON RAIL ASSEMBLY

    Click here

    A

  6. CHECK MIL (ELECTRIC EGR CONTROL VALVE ASSEMBLY)

    1. Disconnect the electric EGR control valve assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY

    Click here

    A

  7. CHECK MIL (DIFFERENTIAL PRESSURE SENSOR ASSEMBLY)

    1. Disconnect the differential pressure sensor assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE DIFFERENTIAL PRESSURE SENSOR ASSEMBLY

    Click here

    A

  8. CHECK MIL (MANIFOLD ABSOLUTE PRESSURE SENSOR)

    1. Disconnect the manifold absolute pressure sensor connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR

    Click here

    A

  9. CHECK MIL (CAMSHAFT POSITION SENSOR)

    1. Disconnect the camshaft position sensor connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE CAMSHAFT POSITION SENSOR

    Click here

    A

  10. CHECK MIL (OIL PRESSURE SENDER GAUGE ASSEMBLY)

    1. Disconnect the oil pressure sender gauge assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE OIL PRESSURE SENDER GAGE ASSEMBLY

    Click here

    A

  11. CHECK MIL (NOZZLE VANE POSITION SENSOR)

    1. Disconnect the nozzle vane position sensor connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Result

      Proceed to

      MIL does not illuminate

      A

      MIL illuminates

      B
    B

    REPLACE TURBOCHARGER SUB-ASSEMBLY

    Click here

    A

  12. CHECK HARNESS AND CONNECTOR

    1. Disconnect the accelerator pedal sensor assembly connector.

    2. Disconnect the diesel throttle body assembly connector.

    3. Disconnect the fuel pressure sensor connector.

    4. Disconnect the electric EGR control valve assembly connector.

    5. Disconnect the differential pressure sensor assembly connector.

    6. Disconnect the manifold absolute pressure sensor connector.

    7. Disconnect the camshaft position sensor connector.

    8. Disconnect the oil pressure sender gauge assembly connector.

    9. Disconnect the nozzle vane position sensor connector.

    10. Disconnect the ECM connectors.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A61-55 (VCPA) - Body ground

      Always

      10 kΩ or higher

      A61-57 (VCP2) - Body ground

      Always

      10 kΩ or higher

      B76-97 (VCVL) - Body ground

      Always

      10 kΩ or higher

      B76-68 (VCM) - Body ground

      Always

      10 kΩ or higher

      B76-69 (VCS) - Body ground

      Always

      10 kΩ or higher

      B76-94 (VCEG) - Body ground

      Always

      10 kΩ or higher

      B76-75 (VCPM) - Body ground

      Always

      10 kΩ or higher

      B76-78 (VCG) - Body ground

      Always

      10 kΩ or higher

      B76-93 (VPOP) - Body ground

      Always

      10 kΩ or higher

      B76-101 (VNVC) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR