2Kd-Ftv Engine Control. Dtc P0400 Exhaust Gas Recirculation Flow

The EGR system recirculates exhaust gases, and performs control so that the proper volume of exhaust gas is recirculated to suit all driving conditions. The recirculated gas mixes with the intake air, allowing the EGR system to slow down engine combustion and lower the combustion temperature. This helps reduce NOx emissions.
In order to increase circulation efficiency, the ECM adjusts the lift amount of the EGR valve and throttle valve.

P0400
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Decelerate from a speed of 50 km/h (80 mph) or more (release accelerator pedal for approximately 5 seconds)	Mass air flow rate is not changed when the EGR valve is turned on (1 trip detection logic).	EGR valve stuck EGR valve does not move smoothly Electric vacuum regulating valve assembly Electric vacuum regulating valve assembly circuit EGR blockage in line between exhaust manifold and intake manifold Mass air flow meter Intake system (leaks or blockages) Exhaust system (exhaust gas leaks) ECM

Related Data List
DTC No.	Data List
P0400	MAF MAP Actual EGR Valve Pos. Target EGR position. EGR Close Lrn. Val. EGR Close Learn Val. EGR Close Lrn. Status EGR Lift Sensor Volt %

MONITOR DESCRIPTION

If the electric EGR control valve assembly is forcibly operated but the intake air amount does not vary, the ECM determines that the electric EGR control valve assembly is malfunctioning. The ECM then illuminates the MIL.

Flow malfunction

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).

Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.2Kd-Ftv Engine Control.Ecd System (For Dpf).
Dtc
P0400 Exhaust Gas Recirculation Flow

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedures.
After replacing the ECM, the new ECM needs registration (HILUX_TGN26 RM0000012XK03ZX.html) and initialization (HILUX_TGN26 RM000000TIN04BX.html).

HINT:

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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)

Connect the intelligent tester to the DLC3.

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

Enter the following menus: Powertrain / Engine and ECT / DTC.

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

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

GO TO DTC CHART (HILUX_TGN26 RM0000031HW01YX.html)

A

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

Connect the intelligent tester to the DLC3.

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

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

Turn the tester on.

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

Read the MAF value displayed on the tester while the engine is idling.

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

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

HINT:

If idling continues for 15 minutes or more, the EGR valve target opening angle becomes 0% (EGR valve fully closed). As this makes diagnosis impossible, it becomes necessary to drive the vehicle or to restart the engine.
Before performing the diagnosis, confirm that the EGR valve target opening angle is not 0%.

Result
Active Test	Result	Proceed to
Activate the EGR Valve Close: Off (Open) to on (Closed)	MAF value does not change	A
Activate the EGR Valve Close: Off (Open) to on (Closed)	MAF value changes	B

NOTICE:

As the values shown below may differ 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 vacuum regulating valve assembly or mass air flow meter.

Reference:

EGR Valve Condition (Opening)	Measuring Condition	MAF (Reference)
Open (55%)	Atmosphere pressure: 101 kPa Intake air temperature: 30°C (86°F) Engine coolant temperature: 88°C (190°F)	3.0 to 9.0 gm/s
Close (0%)		13 to 20 gm/s

Go to step 5

A

3.CHECK VACUUM HOSES

Check the vacuum hoses.

OK:: The hoses are not damaged and are securely connected

Go to step 7

OK

4.INSPECT ELECTRIC VACUUM REGULATING VALVE ASSEMBLY

Inspect the electric vacuum regulating valve assembly (HILUX_TGN26 RM0000015DK01OX.html).

HINT:

Before replacing the electric vacuum regulating valve assembly, perform a wire harness inspection and if there are any problems with the wire harness, repair or replace it.

Go to step 8

OK

5.INSPECT ELECTRIC EGR CONTROL VALVE ASSEMBLY (EGR VALVE OPERATION)

Inspect the electric EGR control valve assembly (HILUX_TGN26 RM000002RK7013X.html).

OK:: The valve is not stuck and does not have heavy carbon deposits

Go to step 8

OK

6.CHECK FOR DEPOSIT (EGR PASSAGE)

Check for blockage in the EGR gas passage between the exhaust manifold and electric EGR control valve assembly.

OK:: No blockage in the EGR gas passage

Go to step 10

Go to step 9

7.REPAIR OR REPLACE VACUUM HOSE

Repair or replace the vacuum hose.

Go to step 10

8.REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY

Replace the electric EGR control valve assembly (HILUX_TGN26 RM000002RK901GX.html).

Go to step 10

9.REPAIR OR REPLACE MALFUNCTIONING PARTS

NEXT

10.CHECK WHETHER DTC OUTPUT RECURS (DTC P0400)

Connect the intelligent tester to the DLC3.

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

Clear the DTCs. (HILUX_TGN26 RM000000PDK0SWX.html)

Turn the ignition switch off for 30 seconds or more.

Start the engine and warm it up.

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).

Enter the following menus: Powertrain / Engine and ECT / DTC.

Read the DTCs.

HINT:

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

END