SFI SYSTEM, Diagnostic DTC:P014C, P014D, P015A, P015B

DTC Code DTC Name
P014C A/F Sensor Slow Response - Rich to Lean Bank 1 Sensor 1
P014D A/F Sensor Slow Response - Lean to Rich Bank 1 Sensor 1
P015A A/F Sensor Delayed Response - Rich to Lean Bank 1 Sensor 1
P015B A/F Sensor Delayed Response - Lean to Rich Bank 1 Sensor 1

DESCRIPTION

Tech Tips

Refer to DTC P2195 Click here.

DTC No. DTC Detection Condition Trouble Area
P014C The "Rich to Lean response rate deterioration level*" value is standard or less (2 trip detection logic).

  • Air fuel ratio sensor (sensor 1)

  • Air fuel ratio sensor (sensor 1) heater

  • ECM
P014D The "Lean to Rich response rate deterioration level*" value is standard or more (2 trip detection logic).
P015A The "Rich to Lean delay level*" value is standard or more (2 trip detection logic).
P015B The "Lean to Rich delay level*" value is standard or more (2 trip detection logic).

*: Calculated by ECM based on the air fuel ratio sensor output.

MONITOR DESCRIPTION

After the engine has been warmed up, the ECM carries out air fuel ratio feedback control, and maintains the air fuel ratio at the theoretical level. In addition, after all the preconditions have been met, active air fuel ratio control is carried out for approximately 10 seconds and during active air fuel ratio control, the ECM measures the response of the air fuel ratio sensor by increasing or decreasing a specific injection quantity based on the theoretical air fuel ratio learned during normal air fuel control. The ECM determines whether there is an air fuel ratio sensor malfunction at the mid-point of active air fuel ratio control.

If the air fuel ratio sensor's response ability is reduced, DTC P014C and P014D are output.

If the air fuel ratio sensor output timing is delayed, DTC P015A and P015B are output.

A01HNWVE28

MONITOR STRATEGY

Related DTCs

P014C: Air fuel ratio sensor (sensor 1) response rate (rich to lean response rate)

P014D: Air fuel ratio sensor (sensor 1) response rate (lean to rich response rate)

P015A: Air fuel ratio sensor (sensor 1) response rate (rich to lean delay)

P015B: Air fuel ratio sensor (sensor 1) response rate (lean to rich delay)
Required Sensors/Components (Main) Air fuel ratio sensor
Required Sensors/Components (Related)

Vehicle speed sensor

Crankshaft position sensor
Frequency of Operation Once per driving cycle
Duration 10 to 15 seconds
MIL Operation 2 driving cycles
Sequence of Operation None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored None
Active air fuel ratio control Performing
Active air fuel ratio control is performed when the following conditions are met -
Battery voltage 11 V or higher
Engine coolant temperature 75°C (167°F) or higher
Idle Off
Engine speed 1300 rpm or higher, and less than 2400 rpm
Air fuel ratio sensor status Activated
Fuel-cut Off
Engine load 10% or higher, and less than 70%
Shift position 2nd or more
Catalyst monitor Not yet
Mass air flow 4 gm/sec or more, and less than 16 gm/sec

TYPICAL MALFUNCTION THRESHOLDS

P014C: Air Fuel Ratio Sensor (Bank 1) Response Rate (Rich to Lean Response Rate)
Rich to Lean Response rate deterioration level 0.0237 V or less
P014D: Air Fuel Ratio Sensor (Bank 1) Response Rate (Lean to Rich Response Rate)
Lean to Rich Response rate deterioration level -0.0266 V or higher
P015A: Air Fuel Ratio Sensor (Bank 1) Response Rate (Rich to Lean Delay)
Rich to Lean delay level 409.6 ms or more
P015B: Air Fuel Ratio Sensor (Bank 1) Response Rate (Lean to Rich Delay)
Lean to Rich delay level 425.984 ms or more

MONITOR RESULT

Refer to detailed information in Checking Monitor Status Click here.

P014C: O2 Sensor / RL RES RATE B1S1
Monitor ID Test ID Scaling Unit Description
$01 $93 Multiply by 0.00012 V Rich to Lean response rate deterioration level
P014D: O2 Sensor / LR RES RATE B1S1
Monitor ID Test ID Scaling Unit Description
$01 $94 Multiply by 0.00012 V Lean to Rich response rate deterioration level
P015A: O2 Sensor / RL DELAY B1S1
Monitor ID Test ID Scaling Unit Description
$01 $95 Multiply by 0.001 Second Rich to Lean delay level
P015B: O2 Sensor / LR DELAY B1S1
Monitor ID Test ID Scaling Unit Description
$01 $96 Multiply by 0.001 Second Lean to Rich delay level

CONFIRMATION DRIVING PATTERN

Tech Tips

Performing this confirmation pattern will activate the air fuel ratio sensor response monitor.

A01HNJ4E72

  1. Connect the Techstream to the DLC3.

  2. Turn the ignition switch to ON.

  3. Turn the Techstream on.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  5. Turn the ignition switch off and wait for at least 30 seconds.

  6. Turn the ignition switch to ON and turn the Techstream on.

  7. Enter the following menus: Powertrain / Engine and ECT / Monitor / Current Monitor.

  8. Check that O2 Sensor / Current is Incomplete.

    Tech Tips

    The test values for the test items RL RES RATE B1S1, LR RES RATE B1S1, RL DELAY B1S1 and LR DELAY B1S1 do not exist in the Detail of O2 Sensor monitor at this time (the initial value of "0.000" is indicated in each test item).

  9. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or higher) [A].

  10. Drive the vehicle at a constant speed between 75 and 100 km/h (47 and 62 mph) for 10 minutes [B].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

  11. Check that O2 Sensor / Current becomes Complete.

    Tech Tips

    Check the test values on the Techstream by entering the following menus: Powertrain / Engine and ECT / Monitor / Current Monitor / O2 Sensor / Details / RL RES RATE B1S1, LR RES RATE B1S1, RL DELAY B1S1 and LR DELAY B1S1.

  12. If the monitor item O2 Sensor / Current does not become Complete (if the test values indicated on the Techstream do not change), perform Readiness Monitor Drive Pattern for the air fuel ratio sensor and heated oxygen sensor Click here.

  13. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].

  14. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

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

  16. Input the DTC: P014C, P014D, P015A or P015B.

  17. Check the DTC judgment result.

    Techstream Display Description
    NORMAL

    • DTC judgment completed

    • System normal
    ABNORMAL

    • DTC judgment completed

    • System abnormal
    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions
    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips


    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result is INCOMPLETE or N/A, drive the vehicle again under an increased load and then recheck the judgment result.

  18. If no pending DTC is output, perform a universal trip and check for permanent DTCs Click here.

    Tech Tips


    • If a permanent DTC is output, the system is malfunctioning.

    • If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0031 Click here.

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips


  • A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.

  • A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.

  • Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor farthest away from the engine assembly.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P014C, P014D, P015A OR P015B)


    1. Connect the Techstream to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the Techstream on.

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

    5. Read the DTCs.

      Result
      Result Proceed to
      DTC P014C, P014D, P015A or P015B is output A
      DTC P014C, P014D, P015A or P015B and other DTCs are output B

      Tech Tips

      If any DTCs other than P014C, P014D, P015A or P015B are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)


    1. Inspect the air fuel ratio sensor Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.


    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)


    1. Disconnect the air fuel ratio sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      E19-1 (HA1A) - E26-23 (HA1A) Always Below 1 Ω
      E19-3 (A1A+) - E26-133 (A1A+) Always Below 1 Ω
      E19-4 (A1A-) - E26-134 (A1A-) Always Below 1 Ω
      E19-1 (HA1A) or E26-23 (HA1A) - Body ground Always 10 kΩ or higher
      E19-3 (A1A+) or E26-133 (A1A+) - Body ground Always 10 kΩ or higher
      E19-4 (A1A-) or E26-134 (A1A-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT AIR FUEL RATIO SENSOR


    1. Check that the proper air fuel ratio sensors are installed to the vehicle.

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.


    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  5. PERFORM CONFIRMATION DRIVING PATTERN


    1. Drive the vehicle according to the Confirmation Driving Pattern.


    NEXT

  6. CHECK WHETHER DTC OUTPUT RECURS (DTC P014C, P014D, P015A OR P015B)


    1. Connect the Techstream to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the Techstream on.

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

    5. Read the pending DTCs.

      Result
      Result Proceed to
      DTC P014C, P014D, P015A or P015B are output A
      DTC is not output B

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  7. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.


    NEXT

  8. PERFORM CONFIRMATION DRIVING PATTERN


    1. Drive the vehicle according to the Confirmation Driving Pattern.


    NEXT

  9. CHECK WHETHER DTC OUTPUT RECURS (DTC P014C, P014D, P015A OR P015B)


    1. Connect the Techstream to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the Techstream on.

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

    5. Read the pending DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC P014C, P014D, P015A or P015B are output B

    B

    CHECK ENGINE TO DETERMINE CAUSE OF EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO Click here

    A

    END