DTC Code | DTC Name |
---|---|
P244B | Diesel Particulate Filter Differential Pressure Too High |
DESCRIPTION
Refer to DTC P244A (Click here).
DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
---|---|---|
Engine is running at 4000 rpm with no load for 10 seconds or more. | While driving, Catalyst Differential Pressure becomes more than 0.37 for 3 seconds. (1 trip detection logic) |
Common Inspection Item:
|
DTC No. | Data List |
---|---|
P244B |
|
MONITOR DESCRIPTION
The ECM compares pressure upstream and downstream of the DPNR catalyst to monitor the differential pressure. If the differential pressure is large, the ECM determines that the DPNR catalyst is contaminated or has deteriorated and illuminates the MIL.
INSPECTION PROCEDURE
After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click here).
After replacing the fuel supply pump assembly, the ECM needs initialization (Click here).
After replacing an injector assembly, the ECM needs registration (Click here).
Read freeze frame data using the intelligent tester. 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.
PROCEDURE
READ OUTPUT DTC (RECORD STORED DTC AND FREEZE FRAME DATA)
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.
Record the stored DTC and freeze frame data.
Check Exhaust Fuel Addition FB and Catalyst Differential Press in the freeze frame data.
When the Exhaust Fuel Addition FB value is 1.45 or more, it indicates a high possibility of insufficient temperature increase during PM forced regeneration.
When the Catalyst Differential Press value is 0.37 or more, it indicates a high possibility that DPNR catalyst is clogged.
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P244B)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Read the DTCs.
Result | Proceed to |
---|---|
P244B is output | A |
P244B is output at the same time as P2463* | |
Other relevant DTCs are output | B |
*: When P244B is output at the same time as P2463, perform this diagnostic procedure. When DTC P244B is not output at the same time as P2463 is output, perform the diagnostic procedure for P244C (Click here).
READ VALUE USING INTELLIGENT TESTER (DPF DIFFERENTIAL PRESSURE)
Connect the intelligent tester to the DLC3.
Start the engine and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / DPF Differential Pressure.
Check the DPF Differential Pressure values from idle speed to unloaded maximum engine speed.
Result | Proceed to |
---|---|
DPF Differential Pressure increases as engine speed increases from idle speed | A |
Except above | B |
If DPF Differential Pressure indicates negative pressure for approx. 1 second as shown in the illustration (A) when the engine speed increases, the differential pressure sensor piping of the DPNR catalyst may be clogged.
CLEAN OR REPLACE VACUUM TRANSMITTING HOSE
Even though it has been determined that the vacuum transmitting hose needs to be repaired or cleaned, make sure to perform all diagnostic procedures for DTC P244B before repairing or cleaning it.
CHECK FOR BLACK SMOKE
Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°F) or higher.
Stop the vehicle and allow the engine to idle.
Fully depress the accelerator pedal for 5 seconds, and then release it [A].
Repeat the above procedure [A] 10 times [B].
Check for black smoke emission during procedures [A] and [B].
OK |
---|
Black smoke is emitted less than 5 times. |
Even if the black smoke is very thin, count the number of black smoke emissions if there is any visible smoke.
READ VALUE USING INTELLIGENT TESTER (CATALYST DIFFERENTIAL PRESS)
Connect the intelligent tester to the DLC3.
Start the engine and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Catalyst Differential Press.
Check the value of Catalyst Differential Press at 4000 rpm without load.
Result | Proceed to |
---|---|
Catalyst Differential Press is more than 0.37 | A |
Except above | B |
PERFORM PM FORCED REGENERATION
Clear the DTC and Exhaust Fuel Addition FB value by disconnecting the cable from the negative (-) battery terminal or removing the EFI MAIN No. 2 fuse for 60 seconds or more.
The accumulated PM volume stored in the ECM cannot be initialized using the intelligent tester.
To perform PM forced regeneration, it is necessary to perform initialization of the accumulated PM volume stored in the ECM.
Connect the intelligent tester to the DLC3.
Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°F) or more.
Move the shift lever to N and set the parking brake.
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the DPF Rejuvenate (PM) / Data List / PM Accumulation Ratio.
Perform the Active Test while the vehicle is driven at a constant vehicle speed within 50 to 100 km/h (31 to 62 mph) (transmission in 3rd gear) for more than 15 minutes.
While the "Activate the DPF Rejuvenate (PM)" Active Test is being performed, the accelerator opening angle should be kept as constant as possible.
When you start driving, "DPNR/DPF Status Reju (PM)" on the Data List displays "Compl". However, continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.
Once "PM Accumulation Ratio" drops to 0%, regeneration is complete.
Continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.
Be aware of excessive heat on and around the exhaust pipes during PM forced regeneration.
If PM forced regeneration stops, repair the malfunction that caused it to stop, and perform it again to complete the operation.
PM forced regeneration completes in 15 to 40 minutes.
PM forced regeneration time changes depending on PM Accumulation Ratio and driving conditions.
A fail-safe stops PM forced regeneration if Catalyst Differential Press increases too much during regeneration
Exhaust Temperature B1S2 becomes 500°C (932°F) or more within 20 minutes of PM forced regeneration start.
PM forced regeneration will be stopped if the accelerator pedal is depressed during regeneration. In this case, PM forced regeneration needs to be performed again.
Even if PM forced regeneration stops while it is occurring, the intelligent tester displays Compl (complete) for DPNR/DPF Status Reju (PM).
Result |
---|
PM forced regeneration completes normally. |
REPLACE DPNR CATALYTIC CONVERTER
Even though it has been determined that the DPNR catalytic converter (Exhaust manifold converter sub-assembly) needs to be replaced, make sure to perform all diagnostic procedures for DTC P244B before replacing it.
GO TO DTC CHART
Perform inspection and repair of relevant DTCs (Click here).
CHECK FUEL INJECTION SYSTEM
Check the fuel injection system (Click here).
CHECK INTAKE / EXHAUST SYSTEM
Check the intake/exhaust system (Click here).
CHECK AFTER TREATMENT CONTROL SYSTEM
Check the after treatment control system (Click here).
REPAIR OR REPLACE MALFUNCTIONING PARTS
Repair, replace or clean the following items only when it has been determined necessary based on diagnosis for DTC P244B.
Clean and/or repair the hoses of the differential pressure sensor.
Replace the DPNR catalytic converter (Exhaust manifold converter sub-assembly) (Click here).
Perform Initialization procedure for DPNR catalyst record clear (Click here).
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Clear the DTC and Exhaust Fuel Addition FB value by disconnecting the cable from the negative (-) battery terminal or removing the EFI MAIN No. 2 fuse for 60 seconds or more.
The accumulated PM volume stored in the ECM cannot be initialized using the intelligent tester.
To perform PM forced regeneration, it is necessary to perform initialization of the accumulated PM volume stored in the ECM.
Connect the intelligent tester to the DLC3.
Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°F) or more.
Move the shift lever to N and set the parking brake.
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the DPF Rejuvenate (PM) / Data List / PM Accumulation Ratio.
Perform the Active Test while the vehicle is driven at a constant vehicle speed within 50 to 100 km/h (31 to 62 mph) (transmission in 3rd gear) for more than 15 minutes.
While the "Activate the DPF Rejuvenate (PM)" Active Test is being performed, the accelerator opening angle should be kept as constant as possible.
When you start driving, "DPNR/DPF Status Reju (PM)" on the Data List displays "Compl". However, continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.
Once "PM Accumulation Ratio" drops to 0%, regeneration is complete.
Continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.
Be aware of excessive heat on and around the exhaust pipes during PM forced regeneration.
If PM forced regeneration stops, repair the malfunction that caused it to stop, and perform it again to complete the operation.
PM forced regeneration completes in 15 to 40 minutes.
PM forced regeneration time changes depending on PM Accumulation Ratio and driving conditions.
A fail-safe stops PM forced regeneration if Catalyst Differential Press increases too much during regeneration
Exhaust Temperature B1S2 becomes 500°C (932°F) or more within 20 minutes of PM forced regeneration start.
PM forced regeneration will be stopped if the accelerator pedal is depressed during regeneration. In this case, PM forced regeneration needs to be performed again.
Even if PM forced regeneration stops while it is occurring, the intelligent tester displays Compl (complete) for DPNR/DPF Status Reju (PM).
END