ECD SYSTEM (w/ EGR Cooler), 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

  • When throttle valve remains closed despite ECM's signal to open valve

    (1 trip detection logic)

  • When throttle valve remains open despite ECM's signal to close valve

    (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)

  • ECM

Tech Tips

After confirming DTC P0488, check the throttle position.

Reference:
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 current flowing to the rotary solenoid with a duty ratio. If the throttle valve does not move smoothly or is stuck, the duty ratio used during valve movement control increases or decreases greatly, and the ECM will determine that the throttle valve is malfunctioning and the ECM illuminates the MIL.

A01DYDHE08

WIRING DIAGRAM

A01DVZ4E08

INSPECTION PROCEDURE

Note

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

Tech Tips


  • After warming up the engine, DTC P0488 can be set if 1 second or more passes after quickly accelerating the engine from idling.

  • Read freeze frame data using the intelligent tester. 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 OTHER DTC OUTPUT (IN ADDITION TO DTC P0488)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine / DTC.

    4. Read the DTCs.

      Result
      Display (DTC Output) Proceed to
      P0488 A
      P0488, 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 IF DTC OUTPUT RECURS


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine / DTC / Clear.

    4. Clear the DTCs.

    5. Start the engine and accelerate the engine from idle to 3,000 rpm 3 times quickly.

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

    7. Read the 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 Valve 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 THROTTLE CONTROL MOTOR


    1. A01DZ5GE40

      Disconnect the T1 throttle control motor.

    2. Turn the ignition switch ON.

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

      Standard voltage
      Tester Connection Specified Condition
      B (T1-2) - Body ground 11 to 14 V
      Standard resistance (Check for open)
      Tester Connection Specified Condition
      RSC (T1-3) - Body ground Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01DZSEE22

      Disconnect the T1 throttle control motor connector.

    2. Disconnect the E7 ECM connector.

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

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      RSO (T1-1) - LUSL (E7-4) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      RSO (T1-1) or LUSL (E7-4) - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE DIESEL THROTTLE BODY ASSEMBLY


    1. Replace diesel throttle body assembly Click here.


    NEXT

  6. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menu: Powertrain / Engine / DTC / Clear.

    4. Clear DTCs.

    5. Start the engine and warm it up.

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

    7. Select the following menu items: Powertrain / Engine / DTC.

    8. Read DTCs.

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

    B

    SYSTEM OK

    A

    REPLACE ECM Click here