ECD SYSTEM (w/o DPF), Diagnostic DTC:P0489, P0490

DTC Code DTC Name
P0489 Exhaust Gas Recirculation Control Circuit Low
P0490 Exhaust Gas Recirculation Control Circuit High

DESCRIPTION

The EGR system recirculates exhaust gases in a way that suits every driving condition. The recirculated gas mixes with intake air. Therefore, the EGR system can slow combustion speed and keep the combustion temperature down. This helps reduce NOx emission.

In order to increase EGR circulation efficiency, the ECM adjusts the lift amount of the EGR valve and the throttle valve angle.

P0489
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
5 seconds after engine is started Open or short in electric vacuum regulating valve assembly circuit for 5 seconds or more (1 trip detection logic).

  • Electric vacuum regulating valve assembly

  • Open or short in electric vacuum regulating valve assembly circuit

  • ECM
P0490
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
5 seconds after engine is started Open or short in electric vacuum regulating valve assembly circuit for 5 seconds or more (1 trip detection logic).

  • Electric vacuum regulating valve assembly

  • Open or short in electric vacuum regulating valve assembly circuit

  • ECM
Related Data List
DTC No. Data List
P0489

  • Actual EGR Valve Pos.

  • Target EGR Position
P0490

WIRING DIAGRAM

Refer to DTC P0400 Click here.

INSPECTION PROCEDURE

Note


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

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

PROCEDURE


  1. INSPECT ELECTRIC VACUUM REGULATING VALVE ASSEMBLY


    1. Inspect the electric vacuum regulating valve assembly Click here.


    NG

    REPLACE ELECTRIC VACUUM REGULATING VALVE ASSEMBLY Click here

    OK

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE)


    1. A01BENRE10
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Electric Vacuum Regulating Valve Assembly)

      Disconnect the electric vacuum regulating valve assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      D73-1 - Body ground Ignition switch ON 11 to 14 V

    3. Reconnect the electric vacuum regulating valve assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (ELECTRIC VACUUM REGULATING VALVE ASSEMBLY - ECM)


    1. Disconnect the electric vacuum regulating valve assembly connector.

    2. Disconnect the D70 ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      D73-2 - D70-9 (EGR) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      D73-2 or D70-9 (EGR) - Body ground Always 10 kΩ or higher

    4. Reconnect the electric vacuum regulating valve assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  4. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  5. REPLACE ELECTRIC VACUUM REGULATING VALVE ASSEMBLY


    1. Replace the electric vacuum regulating valve assembly Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  6. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.

      Tech Tips

      If the voltage at the electric vacuum regulating valve assembly connector is not 11 to 14 V, repair or replace the harness and connector between the electric vacuum regulating valve assembly and the EFI relay (including the EFI No. 2 fuse).


    NEXT

  7. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off for 30 seconds or more.

    4. Start the engine.

    5. Idle the engine for 5 seconds or more.

    6. Enter the following menus: Powertrain / Engine and ECT / DTC.

    7. Confirm that the DTC is not output again.


    NEXT

    END