SFI SYSTEM, Diagnostic DTC:P2195, P2196

DTC Code DTC Name
P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)
P2196 Oxygen (A/F) Sensor Signal Stuck Rich (Bank 1 Sensor 1)

DESCRIPTION

The air fuel ratio sensor generates a voltage* that corresponds to the actual air-fuel ratio. This sensor voltage is used to provide the ECM with feedback so that it can control the air-fuel ratio. The ECM determines the deviation from the stoichiometric air-fuel ratio and regulates the fuel injection time. If the air fuel ratio sensor malfunctions, the ECM is unable to control the air-fuel ratio accurately.

The air fuel ratio sensor is of the planar type and is integrated with a heater, which heats the solid electrolyte (zirconia element). This heater is controlled by the ECM. When the intake air volume is low (the exhaust gas temperature is low), a current flows through the heater to heat the sensor in order to facilitate accurate air-fuel ratio detection. In addition, the sensor and heater portions are the narrow type. The heat generated by the heater is conducted to the solid electrolyte through the alumina, thereby accelerating the sensor activation.

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a Three-Way Catalytic Converter (TWC) is used. For the most efficient use of the Three-Way Catalytic Converter (TWC), the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric level.

*: The value changes inside the ECM. Since the air fuel ratio sensor is a current output element, the current is converted into a voltage inside the ECM. Any measurements taken at the air fuel ratio sensor or ECM connectors will show a constant voltage.

B001I0DE26
DTC No. DTC Detection Condition Trouble Area
P2195

Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)


  • (a) Air fuel ratio sensor voltage more than 3.8 V

  • (b) Heated oxygen sensor voltage is 0.21 V or more

  • Open or short in air fuel ratio sensor (Sensor 1) circuit

  • Air fuel ratio sensor (Sensor 1)

  • Air fuel ratio sensor (Sensor 1) heater

  • Intake system

  • Exhaust system

  • Fuel line

  • Fuel pressure

  • Fuel injector assembly

  • ECM
While fuel-cut operation performed (during vehicle deceleration), air fuel ratio sensor current is 2.2 mA or more for 3 seconds (2 trip detection logic)

  • Air fuel ratio sensor (Sensor 1)

  • ECM
P2196

Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)


  • (a) Air fuel ratio sensor voltage less than 2.8 V

  • (b) Heated oxygen sensor voltage is below 0.71 V

  • Open or short in air fuel ratio sensor (Sensor 1) circuit

  • Air fuel ratio sensor (Sensor 1)

  • Air fuel ratio sensor (Sensor 1) heater

  • Intake system

  • Exhaust system

  • Fuel line

  • Fuel pressure

  • Fuel injector assembly

  • ECM
While fuel-cut operation performed (during vehicle deceleration), air fuel ratio sensor current is less than 0.7 mA for 3 seconds (2 trip detection logic)

  • Air fuel ratio sensor (Sensor 1)

  • ECM

Tech Tips


  • When either of these DTCs is stored, check the air fuel ratio sensor output voltage by entering the following menus: Powertrain / Engine and ECT / Data List / All Data / AFS Voltage B1S1.

  • Short-term fuel trim values can also be read using the GTS.

  • The ECM maintains the voltages at the A1A+ and A1A- terminals of the ECM at a constant level. Therefore, the air fuel ratio sensor output voltage cannot be confirmed without using the GTS.

  • If the air fuel ratio sensor is malfunctioning, the ECM stores DTC P2195 or P2196.

MONITOR DESCRIPTION



B001I5NE84

MONITOR STRATEGY

Required Sensors/Components (Main) Air fuel ratio sensor
Required Sensors/Components (Related) Heated oxygen sensor
Frequency of Operation

Continuous: Sensor voltage detection monitor

Once per driving cycle: Sensor current detection monitor
Duration

5 seconds: Sensor voltage detection monitor

3 seconds: Sensor current detection monitor

TYPICAL ENABLING CONDITIONS

Sensor Voltage Detection Monitor
Time after engine start 30 seconds or more
Fuel system status Closed loop
Sensor Current Detection Monitor
Battery voltage 11 V or higher
Atmospheric pressure 76 kPa (570 mmHg) or higher
Air fuel ratio sensor status Activated
Engine coolant temperature 75°C (167°F) or higher
Continuous time of fuel cut 3 to 10 seconds

TYPICAL MALFUNCTION THRESHOLDS

Sensor Voltage Detection Monitor (Lean Side Malfunction P2195)
Rear heated oxygen sensor voltage 0.21 V or higher
Air fuel ratio sensor voltage Higher than 3.8 V
Sensor Voltage Detection Monitor (Rich Side Malfunction P2196)
Rear heated oxygen sensor voltage Below 0.71 V
Air fuel ratio sensor voltage Below 2.8 V
Sensor Current Detection Monitor (Lean Side Malfunction P2195)
Air fuel ratio sensor current 2.2 mA or higher
Sensor Current Detection Monitor (Rich Side Malfunction P2196)
Air fuel ratio sensor current Below 0.7 mA

CONFIRMATION DRIVING PATTERN

B001GUAE01
B001H8DE53

  1. Connect the GTS to the DLC3.

  2. Turn the ignition switch to ON.

  3. Turn the tester on.

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

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

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

  7. Start the engine and warm it up until the ECT reaches 75°C (167°F) or higher [A].

  8. On the tester, enter the following menus to check the fuel-cut status: Powertrain / Engine and ECT / Data List / Idle Fuel Cut.

  9. Drive the vehicle at a speed between 60 and 100 km/h (37 and 63 mph) for at least 10 minutes [B].

    CAUTION:

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

  10. With the shift lever in 2nd gear (for M/T) or 2nd range (for A/T) [C], accelerate the vehicle to 60 km/h (37 mph) or more by depressing the accelerator pedal for at least 10 seconds [D].

    CAUTION:

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

  11. Soon after performing step [D] above, release the accelerator pedal for at least 4 seconds without depressing the brake pedal in order to execute fuel-cut control [E].

    Tech Tips

    Fuel-cut is performed when the following conditions are met:


    • Accelerator pedal is fully released.

    • A/T:

      Engine speed is 2000 rpm or more (fuel injection returns at 1500 rpm).

      M/T:

      Engine speed is 2000 rpm or more (fuel injection returns at 1200 rpm).

  12. Allow the vehicle to decelerate until the vehicle speed decreases to less than 10 km/h (6 mph).

  13. Repeat steps [C] through [E] above at least 3 times in one driving cycle.

  14. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [F].

  15. Read 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.

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

  17. Input the DTC: P2195 or P2196.

  18. Check the DTC judgment result.

    Tester 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 shows INCOMPLETE or N/A, perform steps [B] through [F] again.

WIRING DIAGRAM

B001HNEE01

CAUTION / NOTICE / HINT

Tech Tips


  • DTC P2A00 may be set, when the air-fuel ratio is stuck rich or lean.

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

  • A high A/F 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 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, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO P2195 OR P2196)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Read the DTCs.

      Result
      Result Proceed to
      P2195 or P2196 is output A
      P2195 or P2196 and P0136, P0137 or P0138 are output A
      P2195 or P2196 and other DTCs are output B

      Tech Tips

      If any DTCs relating to the air fuel ratio sensor (DTCs for the air fuel ratio sensor heater or air fuel ratio sensor admittance) are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST


    1. Has the vehicle run out of fuel in the past?


    NO

    READ VALUE USING GTS (OUTPUT VOLTAGE OF AIR FUEL RATIO SENSOR) Click here

    YES

  3. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs Click here.

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

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

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

    9. Input the DTC: P2195 or P2196.

    10. Check the DTC judgment result.

      Result
      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P2195 or P2196 is output) B

    A

    DTC CAUSED BY RUNNING OUT OF FUEL

    B

  4. READ VALUE USING GTS (OUTPUT VOLTAGE OF AIR FUEL RATIO SENSOR)


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

    4. Warm up the air fuel ratio sensor at an engine speed of 2500 rpm for 90 seconds.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.

    6. Perform the Control the Injection Volume for A/F Sensor operation with the engine idling.

    7. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the GTS.

      Tech Tips


      • Change the fuel injection volume within the range of -12.5% to +12.5%.

      • The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

      • If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

      GTS Display (Sensor) Injection Volume Status Voltage

      AFS Voltage B1S1

      (Air fuel ratio)

      		 +12.5% Rich Below 3.1 V

      AFS Voltage B1S1

      (Air fuel ratio)

      		 -12.5% Lean Higher than 3.4 V

      O2S B1S2

      (Heated oxygen)

      		 +12.5% Rich Higher than 0.55 V

      O2S B1S2

      (Heated oxygen)

      		 -12.5% Lean Below 0.4 V
      Result
      Status of AFS Voltage B1S1 Status of O2S B1S2 Air Fuel Ratio Condition and Air Fuel Ratio Sensor Condition Proceed to
      Lean Lean Actual air fuel ratio lean A
      Rich Rich Actual air fuel ratio rich A
      Lean Lean/Rich Air fuel ratio sensor malfunction B
      Rich Lean/Rich Air fuel ratio sensor malfunction B
      Lean/Rich Lean/Rich Normal B

      Lean: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor output voltage (AFS Voltage) is consistently higher than 3.4 V, and the heated oxygen sensor output voltage (O2S) is consistently below 0.4 V.

      Rich: During the Control the Injection Volume for A/F Sensor Active Test, the AFS Voltage is consistently below 3.1 V, and the O2S is consistently higher than 0.55 V.

      Lean/Rich: During the Control the Injection Volume for A/F Sensor Active Test, the output voltage of the heated oxygen sensor alternates correctly.


    B

    REPLACE AIR FUEL RATIO SENSOR Click here

    A

  5. CHECK FOR INTAKE SYSTEM


    1. Check the intake system for vacuum leaks.

      OK
      No leaks in intake system.

      Tech Tips

      Perform "Inspection After Repair" after repairing or replacing the intake system Click here.


    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  6. CHECK FOR EXHAUST GAS LEAK


    1. Check for exhaust gas leaks.

      OK
      No gas leaks.

      Tech Tips

      Perform "Inspection After Repair" after repairing or replacing the exhaust system Click here.


    NG

    REPAIR OR REPLACE EXHAUST SYSTEM

    OK

  7. CHECK FUEL PRESSURE


    1. Check the fuel pressure Click here.


    NG

    CHECK FUEL LINE Click here

    OK

  8. INSPECT FUEL INJECTOR ASSEMBLY


    1. Check the fuel injector assembly (whether fuel volume is high or low, and whether injector pattern is poor) Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly Click here.


    NG

    REPLACE FUEL INJECTOR ASSEMBLY Click here

    OK

  9. 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

  10. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs Click here.

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

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

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

    9. Input the DTC: P2195 or P2196.

    10. Check the DTC judgment result.

      Result
      Result Proceed to
      ABNORMAL (DTC P2195 or P2196 is output) A
      NORMAL (DTC is not output) B

    B

    END

    A

  11. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  12. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTC Click here.

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

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

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

    9. Input the DTC: P2195 or P2196.

    10. Check the DTC judgment result.

      Result
      GTS 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

    NEXT

    END

  13. 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

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs Click here.

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

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

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

    9. Input the DTC: P2195 or P2196.

    10. Check the DTC judgment result.

      Result
      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P2195 or P2196 is output) B

    A

    END

    B

    REPLACE ECM Click here

  15. CHECK FUEL LINE


    1. Check the fuel lines for leaks or blockage.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump Click here.

      Result
      Result Proceed to
      NG A

      OK

      (for 5 door)

      		 B

      OK

      (for 3 door)

      		 C

    A

    REPAIR OR REPLACE FUEL LINE

    B

    REPLACE FUEL PUMP Click here

    C

    REPLACE FUEL PUMP Click here