The exhaust fuel addition injector is mounted on the exhaust port of the cylinder head, and low pressure is provided to the injector by the feed pump in the supply pump. This injector adds fuel by a control signal from the ECM.

This injector is used for two different controls: DPNR catalyst regeneration and nitrogen oxides (NOx) reduction.

Under the DPNR catalyst regeneration control, the injector adds fuel to raise a catalyst temperature.

In the other control, the injector helps the air-fuel ratio become RICH. As a result, NOx in the exhaust gas will be reduced in response to the RICH air-fuel ratio.

HINT:

For more information on the exhaust fuel addition injector and TOYOTA D-CAT (*1):

If P1386 is present, refer to the diagnostic trouble code (DTC) chart for TOYOTA D-CAT .

"Learning value" used in here represents a correction learning value of the fuel addition volume to raise the DPNR (*2) catalyst temperature to a target range.

*1: Diesel Clean Advanced Technology

*2: Diesel Particulate-NOx Reduction system

DTC No.	DTC Detection Condition	Main Trouble Area	Related Trouble Area
P1386	Excess or low fuel addition volume from exhaust fuel addition injector: Air-fuel ratio deviates from a value estimated by ECM while the injector is adding fuel (1 trip detection logic)	Open or short in exhaust fuel addition injector circuit Exhaust fuel addition injector DPNR catalytic converter (Manifold converter sub-assembly)	Open in exhaust temperature sensor circuit A/F sensor Exhaust gas temperature sensor Supply pump assembly Mass air flow meter Fuel leaks in exhaust fuel addition injector Main injector Cylinder compression pressure Valve clearance Valve timing Blockage in air intake system Leakage in air intake system Blockage in exhaust system Leakage in exhaust system Blockage in EGR system Leakage in EGR system ECM
	Low fuel addition volume from exhaust fuel addition injector: Learning value (*3) exceeds standard level (1 trip detection logic)
	Exhaust fuel addition injector nozzle stuck open: Air-fuel ratio becomes RICHER than standard level, or exhaust gas temperature becomes higher than standard level (1 trip detection logic)

*3: Correction learning value of the fuel addition volume to raise the DPNR catalyst temperature to a target range.

HINT:

DTC P2047, P2048 or P2049 will be present if there is an open malfunction in the exhaust fuel addition injector circuit.

If any one of the main injectors has a closed valve malfunction, rough idle will result. Compensatory injection volume learning values of each cylinder can be read by using the intelligent tester. When the value is more than 3.0 mm³, the cylinder is malfunctioning.

Usually compensation injection volume is 3.0 mm³ or less.

MONITOR DESCRIPTION

HINT:

"Learning value" used here represents a correction learning value of the fuel addition volume to raise the DPNR (*4) catalyst temperature to a target range.

*4: Diesel Particulate-NOx Reduction system.

In order to detect malfunctions in the exhaust fuel addition injector, the ECM monitors the air-fuel ratio, DPNR catalytic temperature and learning value.

When the exhaust fuel addition injector adds fuel during NOx reduction, the ECM monitors the air-fuel ratio when the exhaust fuel addition injector adds fuel. If the air-fuel ratio is too RICH or too LEAN against the ECM predetermined air-fuel ratio, the ECM determines that the fuel addition volume is small or large, and illuminates the MIL. For this malfunction, there is no fail-safe operation.

The ECM always monitors the DPNR catalytic converter temperature and the air-fuel ratio. When the temperature becomes higher than its usual level or the air-fuel ratio becomes extremely RICH, the ECM judges that the injector has stuck open and illuminates the MIL. If this malfunction occurs, the ECM enters the fail-safe mode to limit the acceptable vehicle speed to approximately 80 km/h (50 mph) at maximum by limiting the engine power.

During DPNR catalyst regeneration, the ECM monitors the learning value. Normally, the learning value for the DPNR catalyst regeneration is in the vicinity of 1.0. Thus if the learning value is at 1.99 or more for a certain period of time, the ECM judges the fuel addition volume from the injector is insufficient and illuminates the MIL. If this malfunction occurs, the ECM enters the fail-safe mode to limit the acceptable vehicle speed to approximately 80 km/h (50 mph) at maximum by limiting the engine power.

Malfunction Condition by Fail-Safe Operation:
Fail-Safe Operation	Malfunction Condition	Malfunction Detection Condition	Drive Pattern
No fail-safe operation	Low or excess fuel addition volume from the exhaust fuel addition injector	Actual air-fuel ratio deviates from a value estimated by the ECM when the exhaust fuel addition injector adds fuel during NOx reduction	After warming up the engine, perform DPNR REJU (PM) in the ACTIVE TEST menu using the intelligent tester, and drive at constant vehicle speed within 50 to 100 km/h (31 to 62 mph) for more than 15 minutes
Limits engine power by permitting driving at a maximum vehicle speed of approximately 80 km/h (50 mph)	Exhaust fuel addition injector has stuck open	DPNR catalytic converter temperature becomes higher than 800°C (1,472°F) or air-fuel ratio is less than approximately 12.0 : 1 for a couple of seconds	Idling engine for more than 5 minutes (*5)
Limits engine power by permitting driving at a maximum vehicle speed of approximately 80 km/h (50 mph) HINT: DPNR catalyst regeneration is prohibited	Low fuel addition volume from the exhaust fuel addition injector	During DPNR catalyst regeneration, when learning value of 1.99 or more continues for a certain period of time (*6)	After warming up the engine, perform DPNR REJU (PM) in the ACTIVE TEST menu using the intelligent tester, and drive at constant vehicle speed within 50 to 100 km/h (31 to 62 mph) for more than 30 minutes

*5: The DPNR catalytic converter temperature will not reach 800°C (1,472°F) or higher while idling the engine even if the exhaust fuel addition injector has stuck open.

*6: While the DPNR catalyst regeneration is performed, the ECM raises the DPNR catalytic converter temperature to more than 600°C (1,112°F) by adding fuel using the exhaust fuel addition injector. If the temperature does not reach 600°C (1,112°F) during the attempt, the correction learning value of the fuel addition volume increases by increments in order to raise the DPNR catalytic converter temperature to the target range.

Dtc P1386 Injector For Exhaust Fuel Addition. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

WIRING DIAGRAM

Dtc P1386 Injector For Exhaust Fuel Addition. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

HINT:

"Learning value" used in here represents a correction learning value of the fuel addition volume to raise the DPNR catalyst temperature to a target range.

1.CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P1386)

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

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

Read DTCs.

Result:
Display (DTC output) Proceed to
P1386 A
P1386 and other DTCs B

HINT:

If codes other than P1386 are output, perform troubleshooting for those DTCs first.

Go to step 7

A

3.READ VALUE OF INTELLIGENT TESTER (EXHAUST GAS TEMPERATURE)

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON. (Do not start the engine.)

Enter the following menus: Powertrain / Engine / Data List / Initial Exhaust Temp (In) and Initial Exhaust Temp (Out) and read its value displayed on the intelligent tester.

Result:
Temperature Displayed Proceed to
OK (Same value as actual exhaust gas temperature) A
1,000°C (1,832°F) B

HINT:

If there is an open circuit, the intelligent tester indicates 1,000°C (1,832°F).

Go to step 17

B

5.READ VALUE OF INTELLIGENT TESTER (DPNR A/F)

CAUTION:

Stop the engine immediately if there is white smoke or a fuel smell during the following inspection. Fuel may be leaking from the exhaust fuel addition injector.

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Start the engine.

Enter the following menus: Powertrain / Engine / Data List / DPNR A/F.

Read the air-fuel ratio displayed on the tester after idling the engine for 3 minutes.

Result:
A/F Ratio Proceed to
More than 12 A
Less than 12 B

Go to step 17

A

6.READ VALUE OF INTELLIGENT TESTER (EXHAUST GAS TEMPERATURE)

CAUTION:

Stop the engine immediately if there is white smoke or a fuel smell during the following inspection. Fuel may be leaking from the exhaust fuel addition injector.

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Start the engine.

Enter the following menus: Powertrain / Engine / Data List / Initial Exhaust Temp (In) and Initial Exhaust Temp (Out).

Check that exhaust gas temperature is within the specification below.

Result:
Condition Exhaust Gas Temperature
Idling after warming up engine Constant at approximately 50 to 700°C (122 to 1,292°F)

Go to step 13

A

12.CHECK ENGINE CONTROL SYSTEM

Check that there is no abnormality in the main injector, cylinder compression pressure, valve timing, and valve clearance.

Check that there is no leakage or blockage in the air intake, exhaust, and EGR systems.

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

OK

13.INSPECT EXHAUST FUEL ADDITION INJECTOR (INJECTION VOLUME)

Dtc P1386 Injector For Exhaust Fuel Addition. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

Remove the exhaust fuel addition injector.

Attach the exhaust fuel addition injector to a nozzle tester.

SST
09268-41047(95336-08070)
09268-45014(09268-41220)
09268-41150

Apply a pressure of 0.29 MPa (3.0 kgf/cm², 42 psi) to the nozzle tester.

Connect SST (wire) to the exhaust fuel addition injector.

SST
09842-30080

Inspect the injector.

Standard:
Condition Result
Leave the injector undisturbed for 1 minute with fuel pressurized No leakage from the injector
Apply battery voltage to the injector Fuel is emitted from the injector

HINT:

Injection volume after leaving the exhaust fuel addition injector for 10 seconds with the pressurized fuel applied is as follows:

Reference:
25 cm³ (1.5 cu.in.)

The above is a reference value, thus, your reading may differ from this value depending on the measuring conditions etc.

Check that the nozzle of the exhaust fuel addition injector is not clogged.

Reinstall the exhaust fuel addition injector.

REPLACE EXHAUST FUEL ADDITION INJECTOR ASSEMBLY

OK

14.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (DPNR CATALYST REGENERATION)

Clear the learning value by removing the negative battery cable for more than 1 minute.

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Enter the following menus: Powertrain / Engine / Active Test / Activate the DPNR Rejuvenate (PM).

After warming up the engine, drive the vehicle at a constant speed within 50 to 100 km/h (31 to 62 mph) (with smooth throttle operations) for more than 15 minutes.

Enter the following menus: Powertrain / Engine / Data List / AFS FT B1 S1, Initial Exhaust Temp (In), Initial Exhaust Temp (Out) and Exhaust Fuel Addition FB.

Check the exhaust gas temperatures (Initial Exhaust Temp (In) and (Out)) and the learning value (Exhaust Fuel Addition FB).

Result:

Result	Proceed to
Exhaust gas temperature does not become higher than 600°C (1,112°F)	A
Exhaust gas temperature becomes higher than 600°C (1,112°F), and the learning value remains in the vicinity of 1.0	B

CHECK FOR INTERMITTENT PROBLEMS

A

15.REPLACE EXHAUST FUEL ADDITION INJECTOR ASSEMBLY

NEXT

16.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (DPNR CATALYST REGENERATION)

Clear the learning value by removing the negative battery cable for more than 1 minute.

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Enter the following menus: Powertrain / Engine / Active Test / Activate the DPNR Rejuvenate (PM).

After warming up the engine, drive the vehicle at a constant speed within 50 to 100 km/h (31 to 62 mph) (with smooth throttle operations) for more than 15 minutes.

Enter the following menus: Powertrain / Engine / Data List / AFS FT B1 S1, Initial Exhaust Temp (In), Initial Exhaust Temp (Out) and Exhaust Fuel Addition FB.

Check the exhaust gas temperatures (Initial Exhaust Temp (In) and (Out)) and the learning value (Exhaust Fuel Addition FB).

Result:

Result	Proceed to
Exhaust gas temperature does not become higher than 600°C (1,112°F)	A
Exhaust gas temperature becomes higher than 600°C (1,112°F), and the learning value remains in the vicinity of 1.0	B

END

REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY

17.INSPECT EXHAUST FUEL ADDITION INJECTOR (INJECTION VOLUME)

Remove the exhaust fuel addition injector.

Attach the exhaust fuel addition injector to a nozzle tester.

SST
09268-41047(95336-08070)
09268-45014(09268-41220)
09268-41150

Apply a pressure of 0.29 MPa (3.0 kgf/cm², 42 psi) to the nozzle tester.

Connect SST (Wire) to the exhaust fuel addition injector.

SST
09842-30080

Inspect the injector.

Standard:
Condition Result
Leave the injector undisturbed for 1 minute with fuel pressurized No leakage from the injector
Apply battery voltage to the injector Fuel is emitted from the injector

HINT:

Injection volume after leaving the exhaust fuel addition injector for 10 seconds with the pressurized fuel applied as follows:

Reference:
25 cm³ (1.5 cu.in.)

The above is a reference value, thus, your reading may differ from this value depending on the measuring conditions etc.

Check that the nozzle of the exhaust fuel addition injector is not clogged.

Reinstall the exhaust fuel addition injector.

REPLACE EXHAUST FUEL ADDITION INJECTOR ASSEMBLY

GO TO DTC CHART (RELATED TO MAIN INJECTOR DTC P1238)

LEXUS IS250, IS220d / GSE20 ALE20

2AD-FHV ENGINE CONTROL SYSTEM

Lexus IS250 IS220d GSE20 ALE20

ECD SYSTEM

Temperature Displayed	Proceed to
OK (Same value as actual exhaust gas temperature)	A
1,000°C (1,832°F)	B