ECD SYSTEM, Diagnostic DTC:P0627/78

DTC Code DTC Name
P0627/78 Fuel Pump Control Circuit / Open

DESCRIPTION

Refer to the system description Click here.

DTC No. DTC Detection Condition Trouble Area
P0627/78

Open or short in suction control valve circuit for more than 0.5 seconds

(1 trip detection logic)

  • Open or short in suction control valve circuit

  • Suction control valve

  • ECM

Tech Tips


  • For more information on the supply pump (suction control valve) and the common rail system, refer to the system description Click here.

  • When DTC P0627/78 is set, check the internal fuel pressure of the common rail by entering the following menus on the intelligent tester : Powertrain / Engine / Data List / Fuel Press.

Reference
Engine Speed Fuel Pressure
Idling Approximately 25 to 35 MPa
2,500 rpm (No engine load) Approximately 35 to 55 MPa

WIRING DIAGRAM

A01BEDIE01

INSPECTION PROCEDURE

Note


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

  • After replace the supply pump, the ECM needs initialization Click here.

Tech Tips

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. INSPECT SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)


    1. A01BFPJE01

      Disconnect the D47 suction control valve connector.

    2. Measure the resistance of the suction control valve.

      Standard resistance
      1.9 to 2.3 Ω at 20°C (68°F)

    NG

    REPLACE SUCTION CONTROL VALVE

    OK

  2. CHECK HARNESS AND CONNECTOR


    1. A01BBKLE02

      Disconnect the D47 valve connector.

    2. Disconnect the D1 ECM connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance
      Tester Connection Specified Condition
      D47-1 (PCV+) - D1-2 (PCV+) Below 1 Ω
      D47-2 (PCV-) - D1-1 (PCV-) Below 1 Ω
      D47-1 (PCV+) or D1-2 (PCV+) - Body ground 10 kΩ or higher
      D47-2 (PCV-) or D1-1 (PCV-) - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  3. CHECK ECM TERMINAL VOLTAGE (PCV TERMINAL)


    1. A01BFM2E01

      While cranking or idling the engine, check the waveform of the ECM connector using an oscilloscope.

      Standard
      Tester Connection Specified Condition
      D1-2 (PCV+) - D1-1 (PCV-) Correct waveform is shown
      Tool Setting 10 V/DIV., 5 msec./DIV.
      Condition Idling or cranking with warm engine

      Tech Tips

      The waveform varies depending on the suction control valve operation.


    NG

    REPLACE ECM

    OK

    CHECK FOR INTERMITTENT PROBLEMS