ECD SYSTEM, Diagnostic DTC:P0301,P0302,P0303 and P0304

DTC Code DTC Name
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected

DESCRIPTION

Tip:

For more information on the injector assemblies and common rail system, refer to System Description.

Click hereClick here

The ECM detects combustion deterioration for a specific cylinder.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0301

Cylinder 1 Misfire Detected

While the engine speed is approximately 1000 rpm, it is detected that the number of misfires of the No. 1 cylinder is equal to or greater than the standard value.

(3 trip detection logic)

  • No. 1 injector assembly

  • Compression pressure

  • Valve timing

  • EGR valve assembly

  • Fuel with low cetane number used

  • Flywheel

  • ECM

Comes on

DTC stored

P0302

Cylinder 2 Misfire Detected

While the engine speed is approximately 1000 rpm, it is detected that the number of misfires of the No. 2 cylinder is equal to or greater than the standard value.

(3 trip detection logic)

  • No. 2 injector assembly

  • Compression pressure

  • Valve timing

  • EGR valve assembly

  • Fuel with low cetane number used

  • Flywheel

  • ECM

Comes on

DTC stored

P0303

Cylinder 3 Misfire Detected

While the engine speed is approximately 1000 rpm, it is detected that the number of misfires of the No. 3 cylinder is equal to or greater than the standard value.

(3 trip detection logic)

  • No. 3 injector assembly

  • Compression pressure

  • Valve timing

  • EGR valve assembly

  • Fuel with low cetane number used

  • Flywheel

  • ECM

Comes on

DTC stored

P0304

Cylinder 4 Misfire Detected

While the engine speed is approximately 1000 rpm, it is detected that the number of misfires of the No. 4 cylinder is equal to or greater than the standard value.

(3 trip detection logic)

  • No. 4 injector assembly

  • Compression pressure

  • Valve timing

  • EGR valve assembly

  • Fuel with low cetane number used

  • Flywheel

  • ECM

Comes on

DTC stored
Table 1. Related Data List

DTC No.

Data List

P0301

P0302

P0303

P0304

  • Cylinder 1 Quantity Compensation

  • Cylinder 2 Quantity Compensation

  • Cylinder 3 Quantity Compensation

  • Cylinder 4 Quantity Compensation

  • Target Common Rail Pressure

  • Common Rail Pressure
Tip:

  • If DTC P0301, P0302, P0303 or P0304 is stored, the following symptoms may appear:

    • Rough idle

    • Poor driveability

  • After confirming DTC P0301, P0302, P0303 or P0304, check the internal fuel pressure on the GTS by entering the following menus: Powertrain / Engine and ECT / Data List / Common Rail Pressure, Target Common Rail Pressure.

WIRING DIAGRAM

Refer to DTC P0201.

Click here

CAUTION / NOTICE / HINT

Note:

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

    Click here

  • After replacing an injector assembly, the ECM needs registration.

    Click here

  • After replacing the EGR valve assembly, the ECM needs initialization.

    Click here

Tip:

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. 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. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0301, P0302, P0303 OR P0304)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

      Powertrain > Engine and ECT > Trouble Codes

    4. Read the DTCs.

      Result

      Result

      Proceed to

      P0301, P0302, P0303 or P0304 is output

      A

      P0301, P0302, P0303 or P0304 and other DTCs are output

      B
      Tip:

      If any DTCs other than P0301, P0302, P0303 or P0304 are output, troubleshoot those DTCs first.

    B

    GO TO DTC CHART

    Click hereClick hereClick here

    A

  2. CHECK HARNESS AND CONNECTOR (ENGINE WIRE HARNESS)

    1. Check the wire harness and connector connections.

      OK

      The wire harness and connectors have been connected securely and there are good connections.

    2. Disconnect the injector assembly connector.

    3. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      X8-2 (#10) - B220-29 (IJ1+)

      Always

      Below 1 Ω

      X8-1 (#1) - B220-59 (IJ1-)

      Always

      Below 1 Ω

      X9-2 (#20) - B220-28 (IJ2+)

      Always

      Below 1 Ω

      X9-1 (#2) - B220-58 (IJ2-)

      Always

      Below 1 Ω

      X10-2 (#30) - B220-27 (IJ3+)

      Always

      Below 1 Ω

      X10-1 (#3) - B220-57 (IJ3-)

      Always

      Below 1 Ω

      X11-2 (#40) - B220-26 (IJ4+)

      Always

      Below 1 Ω

      X11-1 (#4) - B220-56 (IJ4-)

      Always

      Below 1 Ω

      X8-2 (#10) or B220-29 (IJ1+) - Body ground

      Always

      10 kΩ or higher

      X8-1 (#1) or B220-59 (IJ1-) - Body ground

      Always

      10 kΩ or higher

      X9-2 (#20) or B220-28 (IJ2+) - Body ground

      Always

      10 kΩ or higher

      X9-1 (#2) or B220-58 (IJ2-) - Body ground

      Always

      10 kΩ or higher

      X10-2 (#30) or B220-27 (IJ3+) - Body ground

      Always

      10 kΩ or higher

      X10-1 (#3) or B220-57 (IJ3-) - Body ground

      Always

      10 kΩ or higher

      X11-2 (#40) or B220-26 (IJ4+) - Body ground

      Always

      10 kΩ or higher

      X11-1 (#4) or B220-56 (IJ4-) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  3. CHECK INJECTOR ASSEMBLY

    1. Check the installation condition of the injector.

      OK

      Injector is installed correctly.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE INJECTOR ASSEMBLYClick here

    OK

  4. PERFORM ACTIVE TEST USING GTS (ACTUATOR TEST OF EGR-VALVE)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Start the engine.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Actuator Test of EGR-Valve / Data List / Target EGR Position and Actual EGR Valve Pos.

      Powertrain > Engine and ECT > Active Test

      Active Test Display

      Actuator Test of EGR-Valve

      Data List Display

      Target EGR Position

      Actual EGR Valve Pos

    5. Perform the following steps 1 to 4.

    6. Step 1

      1. Perform Actuator Test of EGR-Valve with control value of 0% (opening ratio in %).

      2. Monitor the difference of the control value and EGR valve Actuator Position value (0 +/- 3%). EGR valve must operate within 1 second.

    7. Step 2

      1. Wait for 2 seconds or more.

    8. Step 3

      1. Perform Actuator Test of EGR-Valve with control value of 94% (opening ratio in %).

      2. Monitor the difference of the control value and EGR valve Actuator Position value (0 +/- 3%). EGR valve must operate within 1 second.

    9. Step 4

      1. Wait for 2 seconds or more.

    10. Perform the above steps 1 to 4 and check that the part operates as specified.

      OK

      Part operates as specified.

    11. Check the EGR valve for operation malfunctions and whether it is fully closed.

      OK

      EGR valve is moving correctly and fully closed.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE EGR VALVE ASSEMBLYClick here

    OK

  5. CHECK CYLINDER COMPRESSION PRESSURE

    1. Check the cylinder compression pressure.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSIONClick here

    OK

  6. CHECK FUEL QUALITY

    1. Check the fuel quality.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE FUELClick here

    OK

  7. CHECK ENGINE MOUNTING INSULATOR

    1. Check the engine mounting insulator for deformation.

      OK

      Engine mounting insulator is not deformation.

      Tip:

      There are discernible vibrations when the engine is running.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ENGINE MOUNTING INSULATORClick here

    OK

  8. CHECK FLYWHEEL ASSEMBLY

    1. Check the flywheel for deformation and deviation.

      OK

      Flywheel is not deformation and not deviation.

      Tip:

      • There are discernible vibrations when the engine is running.

      • If there are no malfunctions up to this step, DTCs may be stored due to vehicle vibrations. Clear the DTCs once and perform a drive test.

    Result

    Proceed to

    OK

    NG
    OK

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

    NG

  9. REPLACE FLYWHEEL ASSEMBLY

    1. Replace the flywheel assembly.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  10. REPLACE ENGINE MOUNTING INSULATOR

    1. Replace the engine mounting insulator.

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  11. REPLACE FUEL

    1. Replace the fuel.

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  12. CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  13. REPLACE EGR VALVE ASSEMBLY

    1. Replace the EGR valve assembly.

      Click here

    2. Perform EGR learning value reset.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  14. REPLACE INJECTOR ASSEMBLY

    1. Replace the injector assembly.

      Click here

    2. Register the injector assembly compensation code.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  15. REPAIR OR REPLACE HARNESS OR CONNECTOR

    1. Repair or replace the harness or connector.

    Result

    Proceed to

    NEXT
    NEXT

  16. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Perform road test [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

      Powertrain > Engine and ECT > Trouble Codes

    8. Confirm that the DTC is not output again.

    Result

    Proceed to

    NEXT
    NEXT

    END