ECD SYSTEM(w/ Glow Plug Controller) 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, +B2, +B3 (BATT) terminal to operate the microprocessor. The ECM also provides this power to the sensors through the VC output circuit.

A257439E03

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 to ON. The MIL turns off when the engine is started.

WIRING DIAGRAM

A295004E04
A295005E02

CAUTION / NOTICE / HINT

Note:

When replacing the ECM, perform ECM Initialization and Registration.

Click here

Tip:

When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing a new ECM, perform all of the initialization and registration procedures for the "Learning Values Write" function by following the instructions shown on the GTS display.

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

    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

    A
  3. CHECK MIL (THROTTLE POSITION SENSOR)

    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

    A
  4. 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

    A
  5. 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

    A
  6. CHECK MIL (DIESEL TURBO PRESSURE SENSOR)

    1. Disconnect the diesel turbo 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 DIESEL TURBO PRESSURE SENSOR

    A
  7. CHECK MIL (NOZZLE VANE POSITION SENSOR (TURBOCHARGER SUB-ASSEMBLY)

    1. Disconnect the nozzle vane position sensor (turbocharger sub-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 TURBOCHARGER SUB-ASSEMBLY (NOZZLE VANE POSITION SENSOR)

    A
  8. CHECK MIL (DIFFERENTIAL PRESSURE SENSOR)

    1. Disconnect the differential 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 DIFFERENTIAL PRESSURE SENSOR

    A
  9. 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 GAUGE ASSEMBLY

    A
  10. CHECK MIL (FUEL PRESSURE SENSOR (COMMON RAIL ASSEMBLY))

    1. Disconnect the fuel pressure sensor (common rail 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 COMMON RAIL ASSEMBLY (FUEL PRESSURE SENSOR)

    A
  11. 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

    A
  12. CHECK HARNESS AND CONNECTOR (VC CIRCUIT)

    1. Disconnect the diesel throttle body assembly connector.

    2. Disconnect the electric EGR control valve assembly connector.

    3. Disconnect the accelerator pedal sensor assembly connector.

    4. Disconnect the diesel turbo pressure sensor connector.

    5. Disconnect the nozzle vane position sensor (turbocharger sub-assembly) connector.

    6. Disconnect the differential pressure sensor connector.

    7. Disconnect the fuel pressure sensor (common rail assembly) connector.

    8. Disconnect the camshaft position sensor connector.

    9. Disconnect the oil pressure sender gauge assembly connector.

    10. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B212-65 (VCTA) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-64 (VCEG) - Body ground and other terminals

      Always

      10 kΩ or higher

      A169-27 (VCPA) - Body ground and other terminals

      Always

      10 kΩ or higher

      A169-28 (VCP2) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-63 (VPIM) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-67 (VNVC) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-71 (VCPX) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-70 (VCS) - Body ground and other terminals

      Always

      10 kΩ or higher

      B212-68 (VCG) - Body ground and other terminals

      Always

      10 kΩ or higher

      A169-132 (VPOP) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG

    OK

    REPLACE ECM

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR