ECD SYSTEM (for DPF), Diagnostic DTC:P20CF

DTC Code DTC Name
P20CF Exhaust Aftertreatment Fuel Injector "A" Stuck Open

DESCRIPTION

Refer to DTC P200C Click here.

P20CF
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
PM forced regeneration

AF Lambda B1S1 is less than 0.85 for a certain time while the engine is running

(1 trip detection logic)


  • Open or short in exhaust fuel addition injector assembly circuit

  • Exhaust fuel addition injector assembly

  • Fuel filter element sub-assembly


    Common Inspection Item:

  • Fuel injection system

  • Intake/Exhaust system

  • After treatment control system

Related Data List
DTC No. Data List
P20CF/94

AF Lambda B1S1

Exhaust Temperature B1S2

Exhaust Temperature B1S3

MONITOR DESCRIPTION

The ECM monitors the air fuel ratio to detect whether the exhaust fuel addition injector assembly is stuck open.

If the air fuel ratio becomes too rich, the ECM determines that the exhaust fuel addition injector assembly is stuck open, illuminates the MIL and limits engine output.

A01ITLDE01

INSPECTION PROCEDURE

Note


  • Inspect the fuses of circuits related to this system before performing the following 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.

Tech Tips

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


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P20CF)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

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

    5. Read the DTCs.

      Result
      Result Proceed to
      P20CF is output A
      P20CF and other DTCs are output B

      Tech Tips


      • When DTC P20CF and following DTCs are output, uncombusted fuel adhesion to the air fuel ratio sensor due to air fuel ratio sensor malfunction, fuel leaks, insufficient combustion due to parts malfunction (intake, exhaust or injection system), or an exhaust fuel addition injector assembly wiring malfunction is suspected as a cause. Therefore, diagnose the following DTCs first.

      • DTCs for the air fuel ratio sensor are P2237, P2238, P2239, P2252 and P2253 Click here.

      • A DTC for fuel leakage is P0093 Click here.

      • DTCs for the exhaust fuel addition injector assembly wiring malfunction is P20CD Click here.

      • A DTC for EGR valve flow malfunction is P0400 Click here.

      • A DTC for EGR valve stuck open is P042E Click here.


    B
    A
  2. CHECK FOR WHITE SMOKE (WHITE SMOKE AND ODOR)

    Note

    If a fuel odor is noted from the white smoke during the inspection, fuel leaks from the exhaust fuel addition injector assembly are suspected.


    1. Disconnect the cable from the negative (-) battery terminal or remove the EFI MAIN No. 2 fuse for 1 minute or more.

    2. Start the engine and race it to 3000 rpm several times.

    3. Check for white smoke in the exhaust gas. If found, check for a fuel odor or the smell of burning oil.

      Result
      Result Proceed to
      White smoke and a fuel odor are present. A
      White smoke and a smell of burning oil are present. B
      Except above C

    B
    C
    A
  3. PERFORM CONFIRMATION DRIVING PATTERN (WHITE SMOKE AND SENSORY INSPECTION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / AF Lambda B1S1 and Exhaust Temperature B1S3.

    5. Drive the vehicle until the value of Exhaust Temperature B1S3 becomes 300°C (572°F) or more to activate the air fuel ratio sensors.

    6. Check that there is no problem on driving performance such as hesitation, knocking, rough idling, insufficient power and acceleration stumbling, or white smoke in emissions.

      Tech Tips


      • The air fuel ratio sensor does not operate until the vehicle has been driven for a period of time with an exhaust gas temperature of 200°C (392°F) or more.

      • Perform diagnosis when the air fuel ratio sensor is operating and active.

      Result
      Result Proceed to
      There is no problem with driving performance such as hesitation, knocking, rough idling, insufficient power or acceleration stumbling, but excessive white smoke is present in the exhaust gas A
      Except above B

      Tech Tips

      If white smoke is present in the exhaust gas without any driving performance problems such as hesitation, knocking, rough idling, insufficient power or acceleration stumbling, fuel injected due to a malfunction in the exhaust fuel addition injector assembly is the suspected cause of the white smoke.


    B
    A
  4. REPLACE EXHAUST FUEL ADDITION INJECTOR ASSEMBLY


    1. Replace the exhaust fuel addition injector assembly Click here.


    NEXT
  5. REPLACE FUEL FILTER ELEMENT SUB-ASSEMBLY


    1. Replace the fuel filter element sub-assembly Click here.


    NEXT
  6. PERFORM PM FORCED REGENERATION


    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. 2 fuse for 1 minute or more.

      Tech Tips


      • 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.

    2. Connect the intelligent tester to the DLC3.

    3. Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°F) or more.

    4. Move the shift lever to N and set the parking brake.

    5. Turn the tester on.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the DPF Rejuvenate (PM) / Data List / PM Accumulation Ratio.

    7. 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.

      Tech Tips


      • 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.

    8. Continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.

      CAUTION:

      Be aware of excessive heat on and around the exhaust pipes during PM forced regeneration.

      Note

      If PM forced regeneration stops, repair the malfunction that caused it to stop, and perform it again to complete the operation.

      Tech Tips


      • 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 B1S3 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.

    NG
    OK
  7. CHECK FUEL INJECTION SYSTEM


    1. Check the fuel injection system Click here.


    NEXT
  8. CHECK INTAKE / EXHAUST SYSTEM


    1. Check the intake/exhaust system Click here.


    NEXT
  9. CHECK AFTER TREATMENT CONTROL SYSTEM


    1. Check the after treatment control system Click here.


    NEXT
  10. GO TO DTC CHART


    1. Perform inspection and repair of relevant DTCs Click here.


    NEXT
  11. CHECK AND REPLACE TURBOCHARGER SUB-ASSEMBLY


    1. Check for oil leaks and white smoke from the turbocharger sub-assembly and perform any necessary repairs Click here.

      Tech Tips

      Other than a malfunction of the turbocharger subassembly, exhaust valve stem oil leaks are suspected.


    NEXT
  12. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    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. 2 fuse for 1 minute or more.

      Tech Tips


      • 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.

    2. Connect the intelligent tester to the DLC3.

    3. Start the engine and drive the vehicle until the engine coolant temperature reaches 60°C (140°F) or more.

    4. Move the shift lever to N and set the parking brake.

    5. Turn the tester on.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the DPF Rejuvenate (PM) / Data List / PM Accumulation Ratio.

    7. 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.

      Tech Tips


      • 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.

    8. Continue to drive the vehicle until "PM Accumulation Ratio" drops to 0%.

      CAUTION:

      Be aware of excessive heat on and around the exhaust pipes during PM forced regeneration.

      Note

      If PM forced regeneration stops, repair the malfunction that caused it to stop, and perform it again to complete the operation.

      Tech Tips


      • 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 B1S3 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).


    NEXT