SFI 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

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 (TWC) and located near the engine assembly.

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 level, 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 the planar type and is integrated with the 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 into 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.

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 TWC is used. For the most efficient use of the TWC, the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric level.

*: Value changes inside the ECM. Since the air fuel ratio sensor is the current output element, a 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.

A0161LRE01
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 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)

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

  • Air fuel ratio sensor heater circuits

  • Intake system

  • Fuel pressure (low pressure side)

  • Fuel pressure (high pressure side)

  • Fuel injector for port injection

  • Fuel injector for direct injection

  • ECM
While fuel-cut operation performed (during vehicle deceleration), air fuel ratio sensor current 3.6 mA or more for 3 seconds (2 trip detection logic)

  • Air fuel ratio sensor

  • ECM

P2196

P2198

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 0.59 V

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

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

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

  • Air fuel ratio sensor heater circuits

  • Intake system

  • Fuel pressure (low pressure side)

  • Fuel pressure (high pressure side)

  • Fuel injector for port injection

  • Fuel injector for direct injection

  • ECM
While fuel-cut operation performed (during vehicle deceleration), air fuel ratio sensor current less than 0.78 mA for 3 seconds (2 trip detection logic)

  • Air fuel ratio sensor

  • ECM

Tech Tips


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

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

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

  • Bank 2 refers to the bank that includes No. 2 cylinder.

  • When any of these DTCs are set, check the air fuel ratio sensor voltage output by entering the following menus: Powertrain / Engine / 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 voltage output cannot be confirmed without using the intelligent tester.

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

MONITOR DESCRIPTION

Sensor voltage detection monitor

Under the air-fuel ratio feedback control, if the air fuel ratio sensor voltage output indicates rich or lean for a certain period of time, the ECM determines that there is a malfunction in the air fuel ratio sensor. The ECM illuminates the MIL and sets a DTC.

Example:

If the air fuel ratio sensor voltage output is less than 2.8 V (very rich condition) and heated oxygen sensor sensor output voltage is below 0.59 V for 5 seconds, the ECM sets DTC P2196 or P2198. Alternatively, if the air fuel ratio sensor voltage output is more than 3.8 V (very lean condition) and HO2 sensor output voltage is 0.21 V or more for 5 seconds, DTC P2195 or P2197 is set.

Sensor current detection monitor

A rich air-fuel mixture causes a low air fuel ratio sensor current, and a lean air-fuel mixture causes a high air fuel ratio sensor current. Therefore, the sensor output becomes low during acceleration, and it becomes high during deceleration with the throttle valve fully closed. The ECM monitors the air fuel ratio sensor current during fuel-cut and detects any abnormal current values.

If the air fuel ratio sensor output is 3.6 mA or more for more than 3 seconds of cumulative time, the ECM interprets this as a malfunction in the air fuel ratio sensor and sets DTC P2195 or P2197 (high-side stuck). If the air fuel ratio sensor output is less than 0.78 mA for more than 3 seconds of cumulative time, the ECM sets DTC P2196 or P2198 (low-side stuck).

A01608IE10

CONFIRMATION DRIVING PATTERN

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

A0160J9E51
A0161DUE90

  1. Connect the intelligent tester to the DLC3.

  2. Turn the engine switch on (IG).

  3. Turn the tester on.

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

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

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

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

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

  9. Drive the vehicle at between 60 and 120 km/h (37 and 75 mph) for at least 10 minutes [B].

    CAUTION:

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

  10. Shift the transmission to 2nd gear [C].

  11. 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.

  12. Soon after performing step [D] above, release the accelerator pedal for at least 5 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.

    • Engine speed is 2500 rpm or more (fuel injection returns at 1000 rpm).

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

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

  15. Enter the following menus: Powertrain / Engine / DTC / Pending.

  16. Read the pending DTC [F].

    Tech Tips


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

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

  17. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

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

  19. 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
    UNKNOWN

    • 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 ABNORMAL, the system has a malfunction.

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

    • If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [B] through [E] again.

  20. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

  21. Check the DTC judgment result.

    Tech Tips


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

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

WIRING DIAGRAM

A01606ZE01

INSPECTION PROCEDURE

Tech Tips

Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F Sensor function provided in the Active Test. The Control the Injection Volume for A/F Sensor 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 for A/F Sensor operation using the intelligent tester.


  1. Connect the intelligent tester to the DLC3.

  2. Start the engine and turn the tester on.

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

  4. On the tester, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor.

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

  6. 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


  • The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.

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

Tester Display (Sensor) Injection Volume Status Voltage

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 +25% Rich Less than 3.1 V

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 -12.5% Lean More than 3.4 V

O2S B1S2 or O2S B2S2

(Heated oxygen)

 +25% Rich More than 0.55 V

O2S B1S2 or O2S B2S2

(Heated oxygen)

 -12.5% Lean Less than 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 A0162ADE01 A0160FEE04 A0162ADE01 A0161P9E01 -
2 A0162ADE01 A015ZP2E01 A0162ADE01 A0161P9E01

  • Air fuel ratio sensor

  • Air fuel ratio sensor heater

  • Air fuel ratio sensor circuit
3 A0162ADE01 A0160FEE04 A0162ADE01 A015ZP2E01

  • Heated oxygen sensor

  • Heated oxygen sensor heater

  • Heated oxygen sensor circuit
4 A0162ADE01 A015ZP2E01 A0162ADE01 A015ZP2E01

  • Injector

  • Fuel pressure

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

Tech Tips


  • 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.

  • 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 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.

  • 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.

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 engine switch on (IG).

    3. Turn the tester on.

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

    5. Read the DTCs.

      Result
      Result Proceed to
      P2195, P2196, P2197 or P2198 A
      "P2195, P2196, P2197 or P2198" and "P0136, P0137, P0138, P0156, P0157 or P0158" are output A
      P2195, P2196, P2197 or P2198 and other DTCs B

      Tech Tips

      If any DTCs relating to the air fuel ratio sensor (DTCs for the A/F 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

    CHECK FOR INTERMITTENT PROBLEMS Click here

    YES

  3. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

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

    6. Turn the engine switch on (IG) and then the tester on.

    7. Start the engine and warm it up.

    8. Drive the vehicle in accordance with the drive pattern described in the Confirmation Driving Pattern.

    9. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

    10. Check the DTC judgement 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 engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

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

    6. Check the value of the air fuel ratio sensor output current during fuel-cut, referring to the Monitor Drive Pattern Detail for Procedure "C" though Procedure "E" in the Confirmation Driving Pattern.

      Tech Tips


      • To measure the air fuel ratio sensor current precisely, perform the fuel-cut operation as long as possible.

      • If it is difficult to measure the sir fuel ratio sensor current, use the snapshot function of the tester.

      Result
      Result Proceed to
      Within normal range (0.78 mA or higher, and below 3.6 mA) A
      Outside normal range (Below 0.78 mA, or 3.6 mA or higher) B

    B

    REPLACE AIR FUEL RATIO SENSOR Click here

    A

  5. READ VALUE USING INTELLIGENT TESTER (OUTPUT VOLTAGE OF AIR FUEL RATIO SENSOR)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine.

    3. Turn the tester 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 / Active Test / Control the Injection Volume.

    6. Perform the Control the Injection Volume 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 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.

      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 Misfire Suspected Trouble Area Proceed to
      Lean Lean Actual air fuel ratio lean May occur

      • PCV valve and hose

      • PCV hose connections

      • Fuel injector blockage

      • Gas leaks from exhaust system

      • Intake system

      • Fuel pressure

      • Mass air flow meter assembly

      • Engine coolant temperature sensor

      		 A
      Rich Rich Actual air fuel ratio rich -

      • Fuel injector leakage or blockage

      • Gas leaks from exhaust system

      • Ignition system

      • Fuel pressure

      • Mass air flow meter assembly

      • Engine coolant temperature sensor

      		 A
      Lean Lean/Rich Air fuel ratio sensor malfunction - Air fuel ratio sensor B
      Rich Lean/Rich Air fuel ratio sensor malfunction - Air fuel ratio sensor 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

    A

  6. CHECK INTAKE SYSTEM


    1. Check the intake system for vacuum leak.

      OK
      No leak from intake system.

    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  7. INSPECT FOR EXHAUST GAS LEAK


    1. Inspect for exhaust gas leaks.

      OK
      No gas leaks.

    NG

    REPAIR OR REPLACE EXHAUST GAS LEAK POINT

    OK

  8. CHECK FUEL PRESSURE (FOR LOW PRESSURE SIDE)


    1. Check the fuel pressure (for low pressure side) Click here.


    NG

    REPAIR OR REPLACE FUEL SYSTEM (FOR LOW PRESSURE SIDE)

    OK

  9. INSPECT FUEL INJECTOR (FOR PORT INJECTION)


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


    NG

    REPLACE FUEL INJECTOR (FOR PORT INJECTION) Click here

    OK

  10. CHECK FUEL PRESSURE (FOR HIGH PRESSURE SIDE)


    1. Check the fuel pressure (for high pressure side) Click here.


    NG

    REPAIR OR REPLACE FUEL SYSTEM (FOR HIGH PRESSURE SIDE)

    OK

  11. INSPECT FUEL INJECTOR (FOR DIRECT INJECTION)


    1. Inspect the fuel injector for direct injection Click here.


    NG

    REPLACE FUEL INJECTOR (FOR DIRECT INJECTION) Click here

    OK

  12. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  13. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

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

    6. Turn the engine switch on (IG) and then the tester on.

    7. Start the engine and warm it up.

    8. Drive the vehicle in accordance with the drive pattern described in the Confirmation Driving Pattern.


    NEXT

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

    5. Check the DTC judgement 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

  15. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  16. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

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

    6. Turn the engine switch on (IG) and then the tester on.

    7. Start the engine and warm it up.

    8. Drive the vehicle in accordance with the drive pattern described in the Confirmation Driving Pattern.


    NEXT

  17. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

    5. Check the DTC judgement 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