ECD SYSTEM, Diagnostic DTC:P0404

DTC Code DTC Name
P0404 Exhaust Gas Recirculation "A" Control Circuit Range / Performance

DESCRIPTION

Refer to P0401 Click here.

Tech Tips

For more information on the EGR control, refer to System Description Click here.

DTC No. DTC Detection Condition Trouble Area
P0404

The control deviation of the EGR exceeds the maximum or minimum limit value for 4 seconds or more

(3 trip detection logic)

  • EGR valve position sensor (EGR valve assembly)

  • Open or short in EGR valve position sensor (EGR valve assembly) circuit

  • Vacuum switching valve assembly

  • EGR cooler bypass switching valve assembly

  • Vacuum system

  • Vacuum hose

  • EGR valve assembly

  • EGR cooler assembly

  • ECM

WIRING DIAGRAM

A01IR66E54

INSPECTION PROCEDURE

Note


  • When replacing the ECM, the ECM needs Registration and Initialization Click here.

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

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips


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

  • 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 HARNESS AND CONNECTOR (EGR VALVE ASSEMBLY - ECM)


    1. Disconnect the EGR valve assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C87-1 (VC) - C84-69 (VCEG) Always Below 1 Ω
      C87-3 (EGLS) - C84-116 (EGLS) Always Below 1 Ω
      C87-2 (E2) - C84-84 (EEGL) Always Below 1 Ω
      C87-1 (VC) or C84-69 (VCEG) - Body ground Always 10 kΩ or higher
      C87-3 (EGLS) or C84-116 (EGLS) - Body ground Always 10 kΩ or higher
      C87-2 (E2) or C84-84 (EEGL) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (VC VOLTAGE)


    1. Disconnect the EGR valve assembly connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      C87-1 (VC) - C87-2 (E2) Ignition switch ON 4.5 to 5.5 V

    NG

    REPLACE ECM Click here

    OK

  3. CHECK VACUUM SYSTEM


    1. Check that there are no leaks in the vacuum system and the hoses are securely connected.

      OK
      No leaks and hoses are securely connected.

    NG

    REPAIR OR REPLACE VACUUM SYSTEM Click here

    OK

  4. INSPECT EGR COOLER BYPASS SWITCHING VALVE ASSEMBLY


    1. Inspect the EGR cooler bypass switching valve assembly Click here.


    NG

    REPLACE EGR COOLER BYPASS SWITCHING VALVE ASSEMBLY Click here

    OK

  5. INSPECT EGR COOLER ASSEMBLY


    1. Inspect the EGR cooler assembly Click here.


    NG

    REPLACE EGR COOLER ASSEMBLY Click here

    OK

  6. INSPECT VACUUM SWITCHING VALVE ASSEMBLY


    1. Inspect the vacuum switching valve assembly Click here.


    NG

    REPLACE VACUUM SWITCHING VALVE ASSEMBLY Click here

    OK

  7. INSPECT EGR VALVE ASSEMBLY


    1. Inspect the EGR valve assembly Click here.


    NG

    REPLACE EGR VALVE ASSEMBLY Click here

    OK

  8. CHECK VACUUM HOSE


    1. Check the vacuum hose for twists or cracks.

      OK
      No twists or cracks.

    NG

    REPAIR OR REPLACE VACUUM HOSE Click here

    OK

  9. REPLACE EGR VALVE ASSEMBLY


    1. Replace the EGR valve assembly Click here.

    2. Perform EGR learning value reset Click here.


    NEXT

  10. CHECK WHETHER DTC OUTPUT RECURS (DTC P0404)


    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs Click here.

    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: Engine and ECT / Trouble Codes.

    8. Read the DTCs.

      Result
      Result Proceed to
      No DTC output A
      DTC P0404 B

    B

    REPLACE ECM Click here

    A

    END

  11. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  12. REPAIR OR REPLACE VACUUM SYSTEM


    1. Repair or replace the vacuum system.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  13. REPLACE EGR COOLER BYPASS SWITCHING VALVE ASSEMBLY


    1. Replace the EGR cooler bypass switching valve assembly Click here.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  14. REPLACE EGR COOLER ASSEMBLY


    1. Replace the EGR cooler assembly Click here.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  15. REPLACE VACUUM SWITCHING VALVE ASSEMBLY


    1. Replace the vacuum switching valve assembly Click here.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  16. REPLACE EGR VALVE ASSEMBLY


    1. Replace the EGR valve assembly Click here.

    2. Perform EGR learning value reset Click here.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  17. REPAIR OR REPLACE VACUUM HOSE


    1. Repair or replace the vacuum hose.


    NEXT

    CHECK WHETHER DTC OUTPUT RECURS Click here

  18. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  19. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs Click here.

    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: Engine and ECT / Trouble Codes.

    8. Confirm that the DTC is not output again.


    NEXT

    END