ECD SYSTEM, 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 either condition below is met:


  • 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.

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.

A01KHRZE08

WIRING DIAGRAM

A01KHEEE01

INSPECTION PROCEDURE

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.

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

Note

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

PROCEDURE


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


    1. Connect the intelligent tester to the DLC3.

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

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

    4. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P0488 A
      P0488 and P0120, 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

    A

  2. CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)


    1. Connect the intelligent tester to the DLC3.

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

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

    4. Clear the 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 menu items: Powertrain / Engine and ECT / DTC.

    8. 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 Position
      Moment when accelerator pedal is further depressed or released at 3,000 rpm Opening angle varies smoothly

    B

    CHECK FOR INTERMITTENT PROBLEMS

    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.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01KIKOE21
      Text in Illustration
      *1 Throttle Control Motor Connector
      *2 ECM Connector
      *a Wire Harness Side
      *b Front View

      Disconnect the T6 throttle control motor connector.

    2. Disconnect the E5 ECM connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connections Specified Conditions
      T6-1 (DUTY) - E5-4 (LUSL) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connections Specified Conditions
      T6-1 (DUTY) or E5-4 (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

  5. REPLACE DIESEL THROTTLE BODY ASSEMBLY


    1. Replace the diesel throttle body assembly Click here.


    NEXT

  6. CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)


    1. Connect the intelligent tester to the DLC3.

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

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

    4. Clear the 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 menu items: Powertrain / Engine and ECT / DTC.

    8. Read the DTC.

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

    B

    SYSTEM OK

    A

    REPLACE ECM