SFI SYSTEM (w/o EGR System), Diagnostic DTC:P2195, P2196, P2197, P2198

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)
P2197 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 2 Sensor 1)
P2198 Oxygen (A/F) Sensor Signal Stuck Rich (Bank 2 Sensor 1)

DESCRIPTION

The air fuel ratio sensor generates 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 level, and regulates the fuel injection duration. If the air fuel ratio sensor malfunctions, the ECM is unable to control the air fuel ratio accurately.

The air fuel ratio sensor is a planar type with an integrated 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), current flows to the heater to heat the sensor, in order to facilitate accurate oxygen concentration detection. In addition, the sensor and heater portions are narrower than the conventional type. The heat generated by the heater is conducted to the solid electrolyte through the alumina, therefore the sensor activation is accelerated.

A three-way catalytic converter is used in order to convert the carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) into less harmful substances. To allow the three-way catalytic converter to function effectively, it is necessary to keep the air fuel ratio of the engine near the stoichiometric air fuel ratio.

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

A01NF5DE01
DTC No. DTC Detection Condition Trouble Area

P2195

P2197

Conditions (a) and (b) continue for 5 seconds or more

(2 trip detection logic):

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

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

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • Intake system

  • Fuel pressure

  • Fuel injector assembly

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

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

P2196

P2198

Conditions (a) and (b) continue for 5 seconds or more

(2 trip detection logic):

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

(b) Heated oxygen sensor voltage is less than 0.59 V.

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • Intake system

  • Fuel pressure

  • Fuel injector assembly

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

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

Tech Tips


  • DTCs P2195 and P2196 indicate malfunctions related to the bank 1 air fuel ratio sensor circuit.

  • DTCs P2197 and P2198 indicate malfunctions related to the bank 2 air fuel ratio sensor circuit.

  • When any of these DTCs are set, check the air fuel ratio sensor output voltage by entering the following menus: Powertrain / Engine and ECT / Data List / All Data / AFS Voltage B1S1 or AFS Voltage B2S1.

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

  • The ECM regulates the voltages at the A1A+, A2A+, A1A- and A2A- terminals of the ECM to a constant level. Therefore, the air fuel ratio sensor output voltage cannot be confirmed without using the intelligent tester.

  • If an air fuel ratio sensor malfunction is detected, the ECM sets a DTC.

WIRING DIAGRAM

A01NEWTE02

CONFIRMATION DRIVING PATTERN

This confirmation driving pattern is used in the "Perform Confirmation Driving Pattern" procedure of the following diagnostic troubleshooting procedure.

A01NHQ0E02
A01NGQOE74

  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the tester on.

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

  5. Turn the power switch off and wait for 30 seconds.

  6. Turn the power switch on (IG) and turn the tester on.

  7. Put the engine in inspection mode Click here.

  8. Start the engine, and warm it up until the engine coolant temperature reaches 75°C (167°F) or more [A].

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

  10. Drive the vehicle at between 60 and 120 km/h (38 and 75 mph) for 10 minutes or more [B].

    CAUTION:

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

  11. Move the shift lever to S, select the S4 range [C].

  12. Accelerate the vehicle to 64 km/h (40 mph) or more by depressing the accelerator pedal for 10 seconds or more [D].

  13. Soon after performing step [D] above, release the accelerator pedal for 5 seconds or more 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.

    • Vehicle speed is 35 km/h (22 mph) or more (fuel injection returns at 1000 rpm).

  14. Allow the vehicle to decelerate until the vehicle speed decreases to less than 10 km/h (6 mph) [F].

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

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

  17. Read the pending DTCs [F].

    Tech Tips


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

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

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

  19. Input the DTC: P2195, P2196, P2197 or P2198.

  20. 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.

INSPECTION PROCEDURE

Tech Tips

Malfunctioning areas can be identified by performing the Control the Injection Volume function provided in the Active Test. The Control the Injection Volume function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume operation using the intelligent tester.


  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the tester on.

  4. Put the engine in inspection mode Click here.

  5. Start the engine.

  6. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.

    Tech Tips

    During charging control, the engine speed is set at idle. Therefore, the engine speed does not increase when depressing the accelerator pedal. In this case, warm up the engine after charging control has completed.

  7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.

  8. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).

  9. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the tester.

Tech Tips


  • Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations.

  • Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

Tester Display

(Sensor)

 Injection Volume Status Voltage

AFS Voltage B1S1

AFS Voltage B2S1

(Air fuel ratio)

 +12% Rich Below 3.1 V
-12% Lean Higher than 3.4 V

O2S B1S2

O2S B2S2

(Heated oxygen)

 +12% Rich Higher than 0.55 V
-12% Lean Below 0.4 V

Note

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.

Case Air Fuel Ratio Sensor (Sensor 1) Output Voltage Heated Oxygen Sensor (Sensor 2) Output Voltage Main Suspected Trouble Area
1 A01NER4E05 A01NEU5E08 A01NER4E05 A01NGBEE06 -
2 A01NER4E05 A01NCSNE01 A01NER4E05 A01NGBEE06

  • Air fuel ratio sensor

  • Air fuel ratio sensor heater

  • Air fuel ratio sensor circuit
3 A01NER4E05 A01NEU5E08 A01NER4E05 A01NCSNE01

  • Heated oxygen sensor

  • Heated oxygen sensor heater

  • Heated oxygen sensor circuit
4 A01NER4E05 A01NCSNE01 A01NER4E05 A01NCSNE01

  • Fuel injector assembly

  • Fuel pressure

  • Gas leak from exhaust system (Air fuel ratio extremely rich or lean)

Note

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

Tech Tips


  • Although the DTC titles say oxygen sensor, these DTCs relate to the air fuel ratio sensor.

  • Sensor 1 refers to the sensor mounted in front of the three-way catalytic converter and located near the engine assembly.

  • DTC P2A00 or P2A03 may be stored when the air-fuel ratio is stuck at a rich or lean value.

  • Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

  • 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.

  • Bank 1 refers to the bank that includes the No. 1 cylinder*.

    *: The No. 1 cylinder is the cylinder which is farthest from the transmission.

  • Bank 2 refers to the bank that does not include the No. 1 cylinder.

  • 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 P2195, P2196, P2197 OR P2198)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

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

    5. Read the DTCs.

      Result
      Result Proceed to
      DTC P2195, P2196, P2197, or P2198 is output A
      "P2195, P2196, P2197, or P2198" and "P0136, P0137, P0138, P0156, P0157 or P0158" are output A
      DTC P2195, P2196, P2197, or P2198 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 INTELLIGENT TESTER (TEST VALUE OF AIR FUEL RATIO SENSOR) Click here

    YES

  3. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off and wait for 30 seconds.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

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

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

    11. Input the DTC: P2195, P2196, P2197 or P2198.

    12. Check the DTC judgment result.

      Result
      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P2195, P2196, P2197 or P2198 is output) B

    B

    READ VALUE USING INTELLIGENT TESTER (TEST VALUE OF AIR FUEL RATIO SENSOR) Click here

    A

    DTC CAUSED BY RUNNING OUT OF FUEL

  4. READ VALUE USING INTELLIGENT TESTER (TEST VALUE OF AIR FUEL RATIO SENSOR)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Put the engine in inspection mode Click here.

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

    7. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / AFS Current B1S1 and AFS Current B2S1.

    8. Check the test value of the air fuel ratio sensor output current during fuel cut.

      Result
      Test Value Proceed to
      Within normal range (0.7 mA or more, and less than 2.2 mA) A
      Outside normal range (Less than 0.7 mA, or 2.2 mA or more) B

    B

    REPLACE AIR FUEL RATIO SENSOR Click here

    A

  5. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode Click here.

    5. Start the engine.

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

      Tech Tips

      During charging control, the engine speed is set at idle. Therefore, the engine speed does not increase when depressing the accelerator pedal. In this case, warm up the engine after charging control has completed.

    7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume.

    8. Perform the Control the Injection Volume operation with the engine idling.

    9. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the tester.

      Tech Tips


      • Change the fuel injection volume within the range of -12.0% to +12.0%. The injection volume can be changed in fine gradations.

      • 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.

      Tester Display (Sensor) Injection Volume Status Voltage

      AFS Voltage B1S1 or AFS Voltage B2S1

      (Air fuel ratio)

      		 +12.0% Rich Below 3.1 V

      AFS Voltage B1S1 or AFS Voltage B2S1

      (Air fuel ratio)

      		 -12.0% Lean Higher than 3.4 V

      O2S B1S2 or O2S B2S2

      (Heated oxygen)

      		 +12.0% Rich Higher than 0.55 V

      O2S B1S2 or O2S B2S2

      (Heated oxygen)

      		 -12.0% Lean Below 0.4 V
      Result
      Status of AFS Voltage B1S1 or AFS Voltage B2S1 Status of O2S B1S2 or O2S B2S2 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 C

      Lean: During the Control the Injection Volume 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 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 Active Test, the output voltage of the heated oxygen sensor alternates correctly.

      Tech Tips

      Refer to "Data List / Active Test" [AFS Voltage B1S1, AFS Voltage B2S1, O2S B1S2 and O2S B2S2] Click here.


    B

    REPLACE AIR FUEL RATIO SENSOR Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  6. CHECK INTAKE SYSTEM


    1. Check the intake system for vacuum leaks Click here.

      OK
      No leaks in intake system.

    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  7. CHECK FOR EXHAUST GAS LEAK


    1. Check for exhaust gas leaks.

      OK
      No gas leaks.

    NG

    REPAIR OR REPLACE EXHAUST SYSTEM

    OK

  8. CHECK FUEL PRESSURE


    1. Check the fuel pressure Click here.


    NG

    CHECK FUEL LINE Click here

    OK

  9. 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.


    NG

    REPLACE FUEL INJECTOR ASSEMBLY Click here

    OK

  10. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  11. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off and wait for 30 seconds.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

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

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

    11. Input the DTC: P2195, P2196, P2197 or P2198.

    12. Check the DTC judgment result.

      Result
      Result Proceed to
      ABNORMAL (DTC P2195, P2196, P2197 or P2198 is output) A
      NORMAL (DTC is not output) B

    B

    END

    A

  12. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  13. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTC Click here.

    5. Turn the power switch off and wait for 30 seconds.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

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

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

    11. Input the DTC: P2195, P2196, P2197 or P2198.

    12. Check the DTC judgment result.

      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

    NEXT

    END

  14. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  15. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off and wait for 30 seconds.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

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

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

    11. Input the DTC: P2195, P2196, P2197 or P2198.

    12. Check the DTC judgment result.

      Result
      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P2195, P2196, P2197 or P2198 is output) B

    B

    REPLACE ECM Click here

    A

    END

  16. CHECK FUEL LINE


    1. Check the fuel lines for leaks or blockage.


    NG

    REPAIR OR REPLACE FUEL LINE

    OK

    REPLACE FUEL PUMP Click here