Dtc P0488 Exhaust Gas Recirculation Throttle Position Control Range / Performance


DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST USING GTS (DIESEL THROTTLE TARGET ANGLE)

REMOVE DEPOSIT (DIESEL THROTTLE BODY ASSEMBLY)

INSPECT DIESEL THROTTLE BODY ASSEMBLY (THROTTLE VALVE MOVEMENT)

CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)

REMOVE DEPOSIT (DIESEL THROTTLE BODY ASSEMBLY)

INSPECT DIESEL THROTTLE BODY ASSEMBLY (THROTTLE VALVE MOVEMENT)

CHECK HARNESS AND CONNECTOR (DIESEL THROTTLE BODY ASSEMBLY - ECM)

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE DIESEL THROTTLE BODY ASSEMBLY

REPLACE ECM

CHECK WHETHER DTC OUTPUT RECURS

DTC P0488 Exhaust Gas Recirculation Throttle Position Control Range / Performance


DESCRIPTION

The ECM opens and closes the throttle valve using a DC motor type actuator. Due to the opening and closing of 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.
Although the DTC title says "Exhaust Gas Recirculation Throttle Position Control Range / Performance", this DTC indicates that the throttle valve is malfunctioning.

P0488
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Perform the following repeatedly for 1 minute: gradually raise the engine speed to 3000 rpm from idling over approximately 10 seconds, and then release the accelerator pedal to return to an idling state.
The throttle actuator activation duty is more than specified value for 30 seconds.
(1 trip detection logic)
  1. Throttle valve stuck
  2. Throttle valve does not move smoothly
  3. Open or short in throttle control motor circuit
  4. ECM

Related Data List
DTC No.
Data List
P0488
  1. Target Throttle Position
  2. Actual Throttle Position
  3. Throttle Motor Duty
  4. Throttle Close Learning Val.

Reference
Condition
Throttle Valve Position
Moment when accelerator pedal is depressed further or released at 3000 rpm
Throttle valve opening angle varies smoothly

MONITOR DESCRIPTION

The ECM opens and closes the throttle valve by adjusting the current flowing to the DC motor 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. The ECM will determine that the throttle valve is malfunctioning and illuminate the MIL.

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gd-Ftv Engine Control.Ecd System. Dtc P0488 Exhaust Gas Recirculation Throttle Position Control Range / Performance


WIRING DIAGRAM

Refer to DTC P0122 (LandCruiser RM00000187N0A9X_03.html).

INSPECTION PROCEDURE

NOTICE:
  1. When cleaning the diesel throttle body assembly, use a piece of cloth soaked with cleaning solvent. Spraying solvent directly onto these parts or soaking the parts in solvent may damage the parts.
  2. After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AUX.html) and initialization (LandCruiser RM000000TIN08HX.html).
HINT:
  1. 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.
1.PERFORM ACTIVE TEST USING GTS (DIESEL THROTTLE TARGET ANGLE)

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG) and turn the GTS on.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Diesel Throttle Target Angle / Data List / Primary / Actual Throttle Position.

  1. When changing the Active Test continuously value to 10, 30, 60, 90, 60, 30 and 10%, check that Actual Throttle Position smoothly changes to the set opening angle.

    OK:
    Value smoothly changes to set opening angle.


NG
Go to step 5
OK


2.REMOVE DEPOSIT (DIESEL THROTTLE BODY ASSEMBLY)

  1. Visually check for deposits in the diesel throttle body assembly. If there are deposits, clean the diesel throttle body assembly.

    NOTICE:
    1. When cleaning the diesel throttle body assembly, use a piece of cloth soaked with cleaning solvent. Spraying solvent directly onto these parts or soaking the parts in solvent may damage the parts.
    2. Extreme care must be taken to prevent the removed deposits from falling into the engine unit during cleaning.

NEXT


3.INSPECT DIESEL THROTTLE BODY ASSEMBLY (THROTTLE VALVE MOVEMENT)

  1. Using your finger, move the throttle valve from the fully open position to the fully closed position and check that it moves smoothly.

    OK:
    Throttle valve moves smoothly.
    NOTICE:
    Take care not to damage the throttle valve or valve housing.


NG
Go to step 9
OK


4.CHECK WHETHER DTC OUTPUT RECURS (DTC P0488)

  1. Start the engine and warm it up.

  1. Connect the GTS to the DLC3.

  1. Turn the GTS on.

  1. Take a snapshot with the GTS.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Diesel Throttle Target Angle / Data List / Primary / Actual Throttle Position.

    HINT:
    The movement of the throttle valve can be determined by performing the following inspection.

  1. When changing the Active Test value continuously to 10, 30, 60, 90, 60, 30 and 10%, check that Actual Throttle Position smoothly changes to the set opening angle.

    OK:
    Value smoothly changes to set opening angle.

  1. Perform the following repeatedly for 1 minute: gradually raise the engine speed to 3000 rpm from an idling over approximately 10 seconds, and then release the accelerator pedal to return to an idling state.

  1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

  1. Read the DTCs.

    OK:
    DTC is not output.


NG
Go to step 10
OK

END

5.REMOVE DEPOSIT (DIESEL THROTTLE BODY ASSEMBLY)

  1. Visually check for deposits in the diesel throttle body assembly. If there are deposits, clean the diesel throttle body assembly.

    NOTICE:
    1. When cleaning the diesel throttle body assembly, use a piece of cloth soaked with cleaning solvent. Spraying solvent directly onto these parts or soaking the parts in solvent may damage the parts.
    2. Extreme care must be taken to prevent the removed deposits from falling into the engine unit during cleaning.

NEXT


6.INSPECT DIESEL THROTTLE BODY ASSEMBLY (THROTTLE VALVE MOVEMENT)

  1. Using your finger, move the throttle valve from the fully open position to the fully closed position and check that it moves smoothly.

    OK:
    Throttle valve moves smoothly.
    NOTICE:
    Take care not to damage the throttle valve or valve housing.


NG
Go to step 9
OK


7.CHECK HARNESS AND CONNECTOR (DIESEL THROTTLE BODY ASSEMBLY - ECM)

  1. Disconnect the diesel throttle body assembly connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    r5-5 (VC) - C151-29 (VCVL)
    		Always
    		Below 1 Ω
    r5-6 (VTA) - C151-21 (VLU)
    		Always
    		Below 1 Ω
    r5-3 (E2) - C151-20 (EVLU)
    		Always
    		Below 1 Ω
    r5-2 (M+) - C152-6 (M+)
    		Always
    		Below 1 Ω
    r5-1 (M-) - C152-5 (M-)
    		Always
    		Below 1 Ω
    r5-5 (VC) or C151-29 (VCVL) - Body ground and other terminals
    		Always
    		10 kΩ or higher
    r5-6 (VTA) or C151-21 (VLU) - Body ground and other terminals
    		Always
    		10 kΩ or higher
    r5-3 (E2) or C151-20 (EVLU) - Body ground and other terminals
    		Always
    		10 kΩ or higher
    r5-2 (M+) or C152-6 (M+) - Body ground and other terminals
    		Always
    		10 kΩ or higher
    r5-1 (M-) or C152-5 (M-) - Body ground and other terminals
    		Always
    		10 kΩ or higher

  1. Reconnect the throttle control motor connector.

  1. Reconnect the ECM connector.



OK
Go to step 9
NG


8.REPAIR OR REPLACE HARNESS OR CONNECTOR

  1. Repair or replace the harness or connector.



NEXT
Go to step 11

9.REPLACE DIESEL THROTTLE BODY ASSEMBLY

  1. Replace the diesel throttle body assembly (LandCruiser RM0000013ZD02QX.html).



NEXT
Go to step 11

10.REPLACE ECM

  1. Replace the ECM (LandCruiser RM0000013Z002DX.html).


NEXT


11.CHECK WHETHER DTC OUTPUT RECURS

  1. Start the engine and warm it up.

  1. Turn the engine switch on (IG) and turn the GTS on.

  1. Take a snapshot with the GTS.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Diesel Throttle Target Angle / Data List / Primary / Actual Throttle Position.

    HINT:
    The movement of the throttle valve can be determined by performing the following inspection.

  1. When changing the Active Test value continuously to 10, 30, 60, 90, 60, 30 and 10%, check that Actual Throttle Position smoothly changes to the set opening angle.

    OK:
    Value smoothly changes to set opening angle.

  1. Perform the following repeatedly for 1 minute: gradually raise the engine speed to 3000 rpm from an idling over approximately 10 seconds, and then release the accelerator pedal to return to an idling state.

  1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

  1. Confirm that the DTC is not output.


NEXT

END