Dtc P0400 Exhaust Gas Recirculation Flow

Engine Hybrid System. Land Cruiser. Urj200, 202 Grj200 Vdj200
1Vd-Ftv Engine Control. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

MONITOR DESCRIPTION

INSPECTION PROCEDURE

CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0400)

PERFORM ACTIVE TEST USING GTS (ACTIVATE THE EGR VALVE CLOSE)

READ VALUE USING GTS (MAF)

PERFORM ACTIVE TEST USING GTS

REPLACE MASS AIR FLOW METER

REPLACE EGR VALVE ASSEMBLY

CHECK FOR DEPOSIT (EGR VALVE ASSEMBLY)

REPLACE EGR COOLER

CHECK WHETHER DTC OUTPUT RECURS (DTC P0400)

DTC P0400 Exhaust Gas Recirculation Flow


DESCRIPTION

The EGR system recirculates exhaust gases. The recirculated gas mingles with the intake air so that the EGR system can slow combustion speed and keep the combustion temperature down. This helps reduce NOx emissions.
In order to increase EGR circulation efficiency, the ECM adjusts the EGR valve lift amount and the throttle valve angle.

P0400
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
After warming up the engine, decelerate from a speed of 50 km/h (31 mph) or more (fully release the accelerator pedal for approximately 5 seconds).
Mass air flow rate is not changed when turning on the electric EGR control valve assembly while decelerating.
(2 trip detection logic)
  1. EGR valve deposits
  2. EGR valve passage deposits
  3. EGR cooler
  4. Mass air flow meter

Related Data List
DTC No.
Data List
P0400
  1. MAF
  2. Target EGR Valve Pos
  3. Actual EGR Valve Pos
  4. Target EGR Valve Pos #2
  5. Actual EGR Valve Pos #2

MONITOR DESCRIPTION

If the EGR valve is forcibly operated during deceleration but the intake air amount does not vary, the ECM determines that the EGR valve is malfunctioning. The ECM then illuminates the MIL (2 trip detection logic).

Land Cruiser. Urj200, 202 Grj200 Vdj200.1Vd-Ftv Engine Control.Ecd System (W/ Dpf). Dtc P0400 Exhaust Gas Recirculation Flow


INSPECTION PROCEDURE

NOTICE:
  1. After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click here).
  2. After replacing the fuel supply pump assembly, the ECM needs initialization (Click here).
  3. After replacing an injector assembly, the ECM needs registration (Click here).
HINT:
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.CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0400)

  1. Connect the GTS to the DLC3.

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

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

  1. Read the DTCs.

    Result
    Result
    		Proceed to
    P0400 is output
    		A
    P0400 and other DTCs are output
    		B


B
GO TO DTC CHART (Click here)
A


2.PERFORM ACTIVE TEST USING GTS (ACTIVATE THE EGR VALVE CLOSE)

  1. Connect the GTS to the DLC3.

  1. Start the engine and warm it up, and make sure the A/C switch and all accessory switches are off.

  1. Turn the engine switch off. Wait for 30 seconds, and then restart the engine.

  1. Turn the GTS on.

  1. Enter the following menus: Engine and ECT / Data List / MAF.

  1. Read the MAF value displayed on the GTS while the engine is idling.

  1. Enter the following menus: Engine and ECT / Active Test / Activate the EGR Valve Close.

  1. Read the MAF value when the EGR valve is closed using the Active Test function.

    HINT:
    1. If idling continues for 20 minutes or more, the EGR valve target opening lift amount becomes 0% (EGR valve fully closed). As this makes diagnosis impossible, it becomes necessary to drive the vehicle or to restart the engine.
    2. Before performing the diagnosis, confirm that the EGR valve target opening lift amount is not 0%.
    3. When "Coolant Temp" is 75°C (167°F) or higher during idling, the exhaust gas flows through the EGR cooler. If MAF does not change when the EGR is cut even though the EGR valve is operating normally, the EGR cooler may be clogged.

    Result
    Active Test
    		Result
    		Proceed to
    Activate the EGR Valve Close:
    Off (Open) to On (Closed)
    		MAF value does not change
    		A
    MAF value changes
    		B
    NOTICE:
    As the measured values may differ from those shown below due to factors such as differences in measuring environments and changes in vehicle condition due to aging, do not use these values to determine whether the vehicle is malfunctioning or not.
    HINT:
    The problem may be a temporary one, due to the entry of deposits or foreign matter. Check that there are no deposits or foreign matter in the electric EGR control valve assembly or mass air flow meter.

    Reference:

    EGR Valve Condition (Opening)
    		Measuring Condition
    		MAF (Reference)
    Open (40%)
    1. Atmosphere pressure: 101 kPa
    2. Intake air temperature: 30°C (86°F)
    3. Engine coolant temperature: 88°C (190°F)
    		3 to 10 gm/sec
    Closed (0%)
    		14 to 23 gm/sec


B
Go to step 4
A


3.READ VALUE USING GTS (MAF)

  1. Connect the GTS to the DLC3.

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

  1. Enter the following menus: Engine and ECT / Data List / MAF.

  1. With the engine switch on (IG) and engine stopped, read the value when 30 seconds has elapsed.

    Standard:

    GTS Display
    		Switch Condition
    		Standard
    MAF
    		Engine switch on (IG) (do not start engine)
    		Less than 0.5 gm/sec


NG
Go to step 5
OK


4.PERFORM ACTIVE TEST USING GTS

  1. Connect the GTS to the DLC3.

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

  1. Enter the following menus: Engine and ECT / Active Test / Control the EGR Step Position and Control the EGR Step Position #2.

  1. While continuously changing the Active Test value to 0, 30, 60, 90, 60, 30 and 0%, check that Actual EGR Valve Pos or Actual EGR Valve Pos #2 smoothly changes to the set opening lift amount.

    OK:
    Value smoothly changes to within +/- 10% of set opening lift amount.


OK
Go to step 7

NG
Go to step 6

5.REPLACE MASS AIR FLOW METER

  1. Replace the mass air flow meter (Click here).

    HINT:
    If foreign matter is stuck inside the mass air flow meter, the output characteristics of the mass air flow meter may change, resulting in a malfunction.


NEXT
Go to step 9

6.REPLACE EGR VALVE ASSEMBLY

  1. Replace the No. 1 and No. 2 EGR valve assembly (Click here).

    NOTICE:
    Replace the EGR valve assembly which has movement problems.

NEXT


7.CHECK FOR DEPOSIT (EGR VALVE ASSEMBLY)

  1. Remove the No. 1 and No. 2 EGR valve assembly (Click here).

  1. Visually check for deposits.
    If there are deposits, clean the EGR valve and EGR passage (intake/exhaust manifold, EGR pipes, etc.).

    NOTICE:
    1. When cleaning the EGR valve assembly, make sure the valve is completely closed.
    2. When cleaning the EGR valve assembly, perform initialization procedure (Click here).
    3. Do not forcibly open the valve, as it may be damaged or deformed.
    4. When cleaning the EGR valve assembly, use a piece of cloth soaked with cleaning solvent. Spraying the solvent directly onto these parts or soaking the parts in the solvent may damage the parts.

  1. Reinstall the EGR valve assembly (Click here).


NEXT


8.REPLACE EGR COOLER

  1. Replace the EGR cooler (Click here).


NEXT


9.CHECK WHETHER DTC OUTPUT RECURS (DTC P0400)

  1. Connect the GTS to the DLC3.

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

  1. Clear the DTCs (Click here).

  1. Turn the engine switch off for 30 seconds or more.

  1. Start the engine and warm it up.

  1. Move the shift lever to 2nd gear and decelerate from a speed of 50 km/h (31 mph) or more (fully release the accelerator for approximately 5 seconds or more).

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

  1. Read the DTCs.

    HINT:
    When a DTC is output, the mass air flow meter may be malfunctioning.

NEXT

END