ECD SYSTEM(for CCo) 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 inactivated 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 for several seconds when the ignition switch is first turned ON. The MIL goes off when the engine is started.

WIRING DIAGRAM

A299057E02
A213404E02

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) lights up when turning the ignition switch to ON.

      Result

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    MIL does not illuminate

  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

      Proceed to

      Communication is not possible

      Communication is possible
    Communication is possible

    GO TO MIL CIRCUIT

    Click here

    Communication is not possible

  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

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY

    Click here

    MIL does not illuminate

  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

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE DIESEL THROTTLE BODY ASSEMBLY

    Click here

    MIL does not illuminate

  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

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE COMMON RAIL ASSEMBLY

    Click here

    MIL does not illuminate

  6. CHECK MIL (ELECTRIC EGR CONTROL VALVE ASSEMBLY)

    1. Disconnect the electric EGR valve assembly connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY

    Click here

    MIL does not illuminate

  7. 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

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR

    Click here

    MIL does not illuminate

  8. CHECK MIL (BATTERY CURRENT SENSOR ASSEMBLY)

    1. Disconnect the battery current sensor connector.

    2. Turn the ignition switch to ON.

    3. Check the MIL.

      Result

      Proceed to

      MIL does not illuminate

      MIL illuminates
    MIL illuminates

    REPLACE BATTERY CURRENT SENSOR ASSEMBLY

    Click here

    MIL does not illuminate

  9. 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 manifold absolute pressure sensor connector.

    6. Disconnect the battery current sensor connector.

    7. Disconnect the ECM connectors.

    8. 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

      B76-93 (VCPM) - Body ground

      Always

      10 kΩ or higher

      B76-75 (VCIB) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR