ECD SYSTEM (w/ EGR Cooler Bypass Valve), Diagnostic DTC:P0488

DTC Code DTC Name
P0488 Exhaust Gas Recirculation Throttle Position Control Range / Performance

DESCRIPTION

The ECM opens and closes the throttle valve using a rotary solenoid type actuator. Due to opening and closing the valve, the exhaust gas recirculation volume can be properly controlled. Also, engine vibration and noise will be reduced by closing the valve when the engine is stopped.

DTC No. DTC Detection Condition Trouble Area
P0488

  • The throttle motor activation duty is more than 90% for 20 seconds

    (1 trip detection logic)

  • The throttle motor activation duty is less than 10% for 20 seconds

    (1 trip detection logic)

  • Throttle valve stuck

  • Throttle valve does not move smoothly

  • Open or short in throttle valve circuit

  • Open or short in throttle valve position sensor circuit

  • Throttle position sensor (built in diesel throttle body assembly)

  • EFI3 fuse

  • ECM
Related Data List
DTC No. Data List
P0488

  • Actual Throttle Position

  • Target Throttle Position

  • Throttle Motor Duty

  • Throttle Close Learning Val.

  • Diesel Throttle Learn Status

Tech Tips

After confirming DTC P0488, check the throttle position.

Condition Throttle Valve Position
Moment when accelerator pedal is further depressed or released at 3,000 rpm Opening angle varies smoothly

MONITOR DESCRIPTION

The ECM opens and closes the throttle valve by adjusting the duration of current flowing to the rotary solenoid (duty ratio). If the throttle valve does not move smoothly or is stuck, the duty ratio during the valve movement control increases or decreases greatly, the ECM will determine that the throttle valve has a malfunction and illuminates the MIL.

A01KHEUE01

WIRING DIAGRAM

A01KHAME01

INSPECTION PROCEDURE

Note

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

Tech Tips

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO P0488)


    1. Connect the intelligent tester to the DLC3.

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

    3. Select the following menus: Powertrain / Engine and ECT / DTC.

    4. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P0488 A
      P0488 and P0122 and/or P0123 B

      Tech Tips

      If codes other than P0488 are output, perform troubleshooting for those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)


    1. Connect the intelligent tester to the DLC3.

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

    3. Select the following menus: Powertrain / Engine and ECT / DTC / Clear.

    4. Clear DTCs Click here.

    5. Start the engine and warm it up.

    6. Accelerate the engine quickly from idle to 3,000 rpm and repeat them 3 times.

    7. Select the following menus: Powertrain / Engine and ECT / DTC.

    8. Read DTCs.

      Result
      Display (DTC Output) Proceed to
      P0488 A
      No output B

      Tech Tips

      The normal operation of the throttle valve is as follows.

      Reference
      Condition Throttle Position
      Moment when accelerator pedal is further depressed or released at 3,000 rpm Opening angle varies smoothly

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  3. INSPECT DIESEL THROTTLE BODY ASSEMBLY (THROTTLE CONTROL MOTOR POWER SOURCE)


    1. A01KI0IE34
      Text in Illustration
      *1 Throttle Control Motor Connector
      *a Wire Harness Side

      Disconnect the T6 throttle control motor connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage of the wire harness side connector.

      Standard voltage
      Tester Connection Specified Condition
      T6-2 (+B) - Body ground 11 to 14 V
      Standard resistance (Check for open)
      Tester Connection Specified Condition
      T6-3 (GND) - Body ground Below 1 Ω

    4. Reconnect the throttle control motor connector.


    OK

    CHECK HARNESS AND CONNECTOR (THROTTLE CONTROL MOTOR - ECM) Click here

    NG

  4. CHECK HARNESS AND CONNECTOR (THROTTLE CONTROL MOTOR - EFI MAIN RELAY)


    1. Inspect the EFI3 fuse.


      1. Remove the EFI3 fuse from the R/B No. 2.

      2. Check the EFI3 fuse resistance.

        Standard resistance
        Below 1 Ω

      3. Reinstall the EFI3 fuse.

    2. Check the wire harness between the throttle control motor and EFI MAIN relay.


      1. Disconnect the T6 throttle control motor connector.

      2. Remove the EFI MAIN relay from the R/B No. 2.

      3. Check the resistance.

        Standard resistance (Check for open)
        Tester Connection Specified Condition
        R/B No. 2 (EFI MAIN relay terminal 3) - T6-2 Below 1 Ω
        Standard resistance (Check for short)
        Tester Connection Specified Condition
        R/B No. 2 (EFI MAIN relay terminal 3) or T6-2 - Body ground 10 kΩ or higher

      4. Reconnect the throttle control motor connector.

      5. Reinstall the EFI MAIN relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (THROTTLE CONTROL MOTOR - ECM)


    1. Disconnect the T6 throttle control motor connector.

    2. Disconnect the E11 ECM connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connections Specified Conditions
      T6-1 (DUTY) - E11-15 (LUSL) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connections Specified Conditions
      T6-1 (DUTY) or E11-15 (LUSL) - Body ground 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the throttle control motor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE DIESEL THROTTLE BODY ASSEMBLY


    1. Replace the diesel throttle body assembly Click here.


    NEXT

  7. CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)


    1. Connect the intelligent tester to the DLC3.

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

    3. Select the following menus: Powertrain / Engine and ECT / DTC / Clear.

    4. Clear DTCs Click here.

    5. Start the engine and warm it up.

    6. Accelerate the engine quickly from idle to 3,000 rpm and repeat them 3 times.

    7. Select the following menus: Powertrain / Engine and ECT / DTC.

    8. Read DTCs.

      Result
      Display (DTC Output) Proceed to
      P0488 A
      No output B

    B

    SYSTEM OK

    A

    REPLACE ECM Click here