DTC    P244A    Diesel Particulate Filter Differential Pressure Too Low

for Preparation Click here


DESCRIPTION

Refer to DTC P2454 (Click here).

HINT:
If the DPF catalytic converter is melted away or is removed due to a modification, the ECM interprets this as abnormal pressure difference, DTC P244A will be stored and the MIL will be illuminated.


P244A 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Drive the vehicle at an engine speed of 2000 rpm or more, then 3/4 to fully depress the accelerator pedal for 5 seconds (shift position: 4th).
The differential pressure indicates 0 kPa or less for 2 seconds or more
(1 trip detection logic)
  1. Incorrect vacuum transmitting hose routing
  2. Vacuum transmitting hose is clogged
  3. Blockage in transmitting pipe
  4. Differential pressure sensor
  5. Exhaust tail pipe assembly (DPF catalytic converter)
  6. Exhaust system modification

DTC No.
Data List
P244A
DPF Differential Pressure

HINT:
  1. DTC P2454 (Differential pressure sensor circuit low) and/or DTC P2455 (Differential pressure sensor high) will be present if there is an open or short in the differential pressure sensor circuit.
  2. This DTC may also be stored due to the fail-safe operation of the other DTCs.


INSPECTION PROCEDURE

NOTICE:
When replacing the DPF catalyst, the ECM needs Registration and Initialization (Click here).

HINT:
  1. 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.
  2. Check the DPF Differential Pressure using the intelligent tester by entering the following menus: Powertrain / Engine and ECT / Data List / DPF Differential Pressure. For reference, results of real-vehicle check is as shown in the table below:
    DPF Differential Pressure (Result of Real-Vehicle Check) 
    Condition
    		DPF Differential Pressure
    Idling (warm up the engine)
    		0.496 kPa
    Running without load (2500 rpm)
    		0.898 kPa
    Running without load (4500 rpm)
    		2.597 kPa
    Driving in 3rd gear 60 km/h (37 mph)
    		1.40 kPa
    Driving in 3rd gear 60 km/h (37 mph) during PM regeneration
    		3.30 kPa
    Driving with the accelerator fully open at 2000 rpm
    		2.097 kPa
    Driving with the accelerator fully open at 3000 rpm
    		3.097 kPa
    Driving with the accelerator fully open at 4500 rpm
    		3.097 kPa

1.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P244A)

  1. Connect the intelligent tester to the DLC3.

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

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

  1. Read the DTCs.
    Result 
    Result
    		Proceed to
    P244A
    		A
    P244A and other DTCs
    		B

    HINT:
    If DTCs other than P244A are output, perform troubleshooting for those DTCs first.



B
GO TO DTC CHART (Click here)
A


2.CHECK CONNECTION OF VACUUM TRANSMITTING HOSE ASSEMBLY (DIFFERENTIAL PRESSURE SENSOR - TRANSMITTING PIPE)

CAUTION:
Be careful of being burned by exhaust gases during the following inspection.

NOTICE:
  1. Confirm the paint marks on the vacuum transmitting hoses before disconnecting them.
  2. Check that the vacuum transmitting hose connections are on the correct side of the DPF/DPNR catalytic converter.



  1. Disconnect the vacuum transmitting hose (both upstream and downstream) on the differential pressure sensor side.


    A200355E01

  1. Start the engine.

  1. Check if there is exhaust gas pulsation from both vacuum transmitting hoses while the engine is idling.

    OK:
    The vacuum transmitting hose connections are correct and there is no leak or blockage.



NG
Go to step 7
OK


3.CHECK EXHAUST SYSTEM

  1. Check for exhaust gas leak from the exhaust system.

  1. Check for exhaust system modifications.

    OK:
    No exhaust gas leak and no modifications.



NG
Go to step 8
OK


4.INSPECT DIFFERENTIAL PRESSURE SENSOR ASSEMBLY

  1. Inspect the differential pressure sensor (Click here).

    Standard:
    Approximately the same pressure as the applied pressure is indicated.

    HINT:
    The DPF Differential Pressure display is a value that does not reflect the zero point adjustment. Therefore the displayed value will be about 0.3 kPa even if the applied differential pressure is 0.



NG
Go to step 9
OK


5.PERFORM DIFFERENTIAL PRESSURE SENSOR LEARNING

  1. Start the engine and wait until the engine coolant temperature reaches 75°C (167°F) or more (A).

  1. Turn the ignition switch off and wait for 30 seconds or more (B).

  1. Repeat the above procedures (A) and (B) 3 times.

    HINT:
    Procedures (A) and (B) must be repeated 3 times to complete the differential pressure sensor learning process.


NEXT


6.READ VALUE USING INTELLIGENT TESTER (DPF DIFFERENTIAL PRESSURE)

  1. Connect the intelligent tester to the DLC3.

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

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / DPF Differential Pressure.

  1. Read the value.

  1. Start the engine.

  1. Run the engine at 4500 rpm without load.

  1. Compare the value at 4500 rpm with the value at ignition switch ON.

    HINT:
    When read the values of data list, confirm that PM regeneration is not activating (value of "After Injection Period" is 0) by entering the following menus: Powertrain / Engine and ECT / Data List / After Injection Period.
    If PM regeneration is activating (value of "After Injection Period" is not 0), drive the vehicle until the PM regeneration is complete (value of "After Injection Period" becomes 0).

    Standard:
    "DPF Differential Pressure at 4500 rpm" - "DPF Differential Pressure at ignition switch ON" is 1.0 kPa or more.

    Result 
    Result
    		Proceed to
    Less than 1.0 kPa
    		A
    1.0 kPa or more
    		B



A
Go to step 12

B
Go to step 15

7.REPLACE CLOGGED PARTS


NEXT
Go to step 15

8.REPAIR OR REPLACE EXHAUST SYSTEM

  1. Repair or replace the modification in the exhaust system.



NEXT
Go to step 15

9.REPLACE DIFFERENTIAL PRESSURE SENSOR ASSEMBLY

  1. Replace the differential pressure sensor assembly (Click here).

  1. Start the engine and wait until the engine coolant temperature reaches 75°C (167°F) or more (A).

  1. Turn the ignition switch off and wait for 30 seconds or more (B).

  1. Repeat the above procedures (A) and (B) 3 times.

    HINT:
    Procedures (A) and (B) must be repeated 3 times to complete the differential pressure sensor learning process.


NEXT


10.INSPECT DIFFERENTIAL PRESSURE SENSOR ASSEMBLY

  1. Inspect the differential pressure sensor (Click here).

    Standard:
    Approximately the same pressure as the applied pressure is indicated.

    HINT:
    The DPF Differential Pressure display is a value that does not reflect the zero point adjustment. Therefore the displayed value will be about 0.3 kPa even if the applied differential pressure is 0.



OK
Go to step 15

NG
Go to step 11

11.REPLACE ECM

  1. Replace the ECM (Click here).



NEXT
Go to step 15

12.CHECK WHETHER DTC OUTPUT RECURS (DTC P244A)

  1. Connect the intelligent tester to the DLC3.

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

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch off and wait for 30 seconds.

  1. Start the engine.

  1. Drive the vehicle at an engine speed of 2000 rpm or more (C).

  1. In 4th gear, 3/4 to fully depress the accelerator pedal for 5 seconds (D).

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

  1. Read the DTCs.

    HINT:
    Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.

    1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    2. Input DTC P244A.

    3. Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, repeat the procedures (C) and (D).
      Result 
      Result
      		Proceed to
      NORMAL
      		A
      ABNORMAL
      		B



B
Go to step 13
A

CHECK FOR INTERMITTENT PROBLEMS (Click here)  

13.REPLACE EXHAUST TAIL PIPE ASSEMBLY

  1. Replace the exhaust tail pipe assembly (DPF catalytic converter) (Click here).


NEXT


14.PERFORM INITIALIZATION (DPF DETERIORATION RECORD)

  1. Reset the DPF deterioration record (Click here).


NEXT


15.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the intelligent tester to the DLC3.

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

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch off and wait for 30 seconds.

  1. Start the engine.

  1. Drive the vehicle at an engine speed of 2000 rpm or more (C).

  1. In 4th gear, 3/4 to fully depress the accelerator pedal for 5 seconds (D).

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

  1. Confirm that the DTC is not output again.

    HINT:
    Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.

    1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    2. Input DTC P244A.

    3. Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, repeat the procedures (C) and (D).


NEXT

END