Dtc P0420 Catalyst System Efficiency Below Threshold (Bank 1)

DESCRIPTION

MONITOR DESCRIPTION

INSPECTION PROCEDURE

READ OUTPUT DTC (RECORD STORED DTC AND FREEZE FRAME DATA)

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0420, P2458 AND P2463)

GO TO DTC CHART

CHECK FOR BLACK SMOKE

REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY

CHECK FOR WHITE SMOKE (DURING PM FORCED REGENERATION)

REPLACE EXHAUST FUEL ADDITION INJECTOR ASSEMBLY

REPLACE EXHAUST MANIFOLD CONVERTER SUB-ASSEMBLY

CHECK FUEL INJECTION SYSTEM

CHECK INTAKE / EXHAUST SYSTEM

REPAIR OR REPLACE MALFUNCTIONING PARTS

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

DESCRIPTION

HINT:

PM forced regeneration may be prohibited due to a fail-safe operation that is performed when another DTC is stored (including engine output limitation).

MONITOR DESCRIPTION

1. Abnormal DOC catalyst temperature increase:
   The ECM monitors exhaust gas temperature increase while the exhaust fuel addition injector assembly adds fuel during PM forced regeneration. Exhaust gas temperature increases up to approximately 300 to 500°C (572 to 932°F) during PM forced regeneration. If the temperature does not increase even after a certain amount of time has elapsed, the ECM determines that the DOC catalyst is abnormal and illuminates the MIL.
   

1. Catalytic converter Regeneration Duration:
   When PM forced regeneration is manually performed, PM forced generation does not finish even after 60 minutes or more elapse, the ECM determines that there is problem with the DPF catalyst and illuminates the MIL.
   

1. Excessive PM accumulation:
   The ECM monitors the PM Accumulation Ratio and when the accumulated PM volume in the DPF catalyst exceeds the limit, the ECM illuminates the MIL.
   

INSPECTION PROCEDURE

NOTICE:

1. After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AVX.html) and initialization (LandCruiser RM000000TIN08IX.html).
   
2. After replacing an injector assembly, the ECM needs registration (LandCruiser RM0000012XK0AVX.html).
   

HINT:

1. If DTC P0420, P2458 or P2463 is stored, fail-safe controls engine power output and PM forced regeneration is prohibited. In this case, PM forced regeneration can be performed after disconnecting the EFI-MAIN NO. 1 fuse or battery terminal and waiting for 60 seconds or more before connecting it again.
   
2. 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. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG).
   

3. Turn the GTS on.
   

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

5. Record the stored DTC and freeze frame data.
   

6. Check Exhaust Fuel Addition FB and Catalyst Differential Press in the freeze frame data.
   

   HINT:

   1. When the Exhaust Fuel Addition FB value is 1.41 or more, it indicates a high possibility of insufficient temperature increase during PM regeneration control.
      
   2. When the Catalyst Differential Press value is 0.27 or more, it indicates a high possibility that DPF catalyst is clogged.
      

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG).
   

3. Turn the GTS on.
   

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

5. Read the DTCs.
   
   

   Result

   Result	Proceed to
   DTC P0420, P2458 or P2463 is output	A
   DTC P244B is output at the same time as P2463*	B
   Other relevant DTCs are output	C

   HINT:

   1. *: When P244B is output at the same time as P2463, perform troubleshooting for P244B.
      
   2. When DTC P1603, P1604 or P1608 is output in addition to P0420, perform troubleshooting for P1603, P1604 or P1608 first.
      

1. Diagnose relevant DTCs (LandCruiser RM0000031HW07PX.html).
   

1. Start the engine and drive the vehicle until the engine coolant temperature reaches 75°C (167°F) or higher.
   

2. Stop the vehicle and allow the engine to idle.
   

3. Fully depress the accelerator pedal for 5 seconds, and then release it [A].
   

4. Repeat the above procedure [A] 10 times [B].
   

5. Check for black smoke emission during procedures [A] and [B].
   

   OK:

   Black smoke is emitted less than 5 times.
   

   HINT:

   Even if the black smoke is very thin, count the number of black smoke emissions if there is any visible smoke.

1. Even though it has been determined that the exhaust manifold converter sub-assembly (DPF catalyst) needs to be replaced, make sure to perform all diagnostic procedures for P0420, P2458 and P2463 before replacing it.
   

   HINT:

   This DTC is stored because an excessive amount of PM has accumulated and resulted in abnormal combustion. It is necessary to diagnose the cause of abnormal PM accumulation and repair the problem. Therefore, do not perform replacement at this time.

1. Clear the DTC and Exhaust Fuel Addition FB value by disconnecting the cable from the negative (-) battery terminal or removing the EFI-MAIN NO. 1 fuse for 1 minute or more.
   

   HINT:

   1. The accumulated PM volume stored in the ECM cannot be initialized using the GTS.
      
   2. To perform PM forced regeneration, it is necessary to perform initialization of the accumulated PM volume stored in the ECM.
      

2. Connect the GTS to the DLC3.
   

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

4. Enter the following menus: Powertrain / Engine / Trouble Codes.
   

5. Clear the DTCs.
   

6. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
   

7. Maintain the maximum possible engine speed under no load for 10 seconds to blow out all soot from inside the exhaust pipe.
   

   HINT:

   1. If only a low engine speed is continuously maintained, soot may accumulate at the end of the catalyst.
      
   2. When soot accumulates at the end of the catalyst, it may not be possible to perform PM forced regeneration control normally.
      

8. Perform PM forced regeneration.
   

9. Check if the temperature increases or abnormal white smoke occurs during PM forced regeneration.
   
   

   Result

   Result	Proceed to
   During PM forced regeneration, temperature of exhaust temperature sensor B1S2 is 300 to 500°C and no white smoke is generated	A
   During PM forced regeneration, temperature of exhaust temperature sensor B1S2 is 300 to 500°C and abnormal white smoke is generated*1	B
   Other than above*2	C

   HINT:

   1. *1: If abnormal white smoke is only generated during PM forced regeneration, there may be uncombusted fuel due to deterioration of the DPF catalyst.
      
   2. *1: When there is a malfunction with combustion control, operation performance may be reduced and abnormalities may be felt even if PM forced regeneration is performed.
      
   3. *2: An excess of accumulated PM is the result of a malfunction in the control system causing poor combustion and an increase in black smoke.
      

1. Even though it has been determined that the exhaust fuel addition injector assembly needs to be replaced, make sure to perform all diagnostic procedures for P0420, P2458 and P2463 before replacing it.
   

1. Even though it has been determined that the exhaust manifold converter sub-assembly (DPF catalyst) needs to be replaced, make sure to perform all diagnostic procedures for P0420, P2458 and P2463 before replacing it.
   

   HINT:

   This DTC is stored because an excessive amount of PM has accumulated and resulted in abnormal combustion. It is necessary to diagnose the cause of abnormal PM accumulation and repair the problem. Therefore, do not perform replacement at this time.

1. Check the fuel injection system (LandCruiser RM000004KNK023X.html).
   

1. Check the intake/exhaust system (LandCruiser RM000004KNL01TX.html).
   

HINT:

Replace the following items only when it has been determined necessary based on diagnosis for DTC P0420, P2458 and P2463.

1. Replace the exhaust manifold converter sub-assembly (See page ).
   

   NOTICE:

   Perform Initialization procedure for "DPF catalyst record clear" and "DPF Deterioration Record Clear" (See page ).

2. Replace the exhaust fuel addition injector assembly (See page ).
   

3. Repair or replace the malfunctioning part confirmed in the diagnosis of the fuel injection system and intake/exhaust system.
   

1. Connect the GTS to the DLC3.
   

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

3. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

4. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
   

5. Perform PM forced regeneration (See page ).