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DTC    P2195    Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)

DTC    P2196    Oxygen (A/F) Sensor Signal Stuck Rich (Bank 1 Sensor 1)

for Preparation Click here


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 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 the narrow 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), hydrocarbons (HC) and nitrogen oxide (NOx) components in the exhaust gas, a three-way catalytic converter is used. For the most efficient use of the three-way catalytic converter, 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 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.

A234900E01


DTC No.
DTC Detection Condition
Trouble Area
P2195
Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)
  1. (a) Air fuel ratio sensor voltage more than 3.8 V
  2. (b) Heated oxygen sensor voltage is 0.21 V or more
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. Air fuel ratio sensor (sensor 1) heater
  4. Air fuel ratio sensor heater circuit
  5. Intake system
  6. Fuel pressure
  7. Fuel injector assembly
  8. EGR valve assembly
  9. 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)
  1. Air fuel ratio sensor (sensor 1)
  2. ECM
P2196
Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)
  1. (a) Air fuel ratio sensor voltage less than 2.8 V
  2. (b) Heated oxygen sensor voltage is less than 0.59 V
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. Air fuel ratio sensor (sensor 1) heater
  4. Air fuel ratio sensor heater circuit
  5. Intake system
  6. Fuel pressure
  7. Fuel injector assembly
  8. EGR valve assembly
  9. 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)
  1. Air fuel ratio sensor (sensor 1)
  2. ECM

HINT:
  1. When any of these DTCs are set, check the air fuel ratio sensor voltage output by entering the following menus on the intelligent tester: Powertrain / Engine and ECT / Data List / All Data / AFS Voltage B1S1.
  2. Short-term fuel trim values can also be read using the intelligent tester.
  3. The ECM regulates the voltages at the A1A+ and A1A- terminals of the ECM to a constant level. Therefore, the air fuel ratio sensor voltage output cannot be confirmed without using the intelligent tester.
  4. If an air fuel ratio sensor malfunction is detected, the ECM sets a DTC.


WIRING DIAGRAM


A219621E01


CONFIRMATION DRIVING PATTERN

CAUTION:
Strictly observe posted speed limits, traffic laws, and road conditions when performing these drive patterns.

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


A199318E16


A107163E77

  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 higher [A].
  9. On the intelligent tester, enter the following menus to check the fuel-cut status: Powertrain / Engine and ECT / Data List / All Data / Idle Fuel Cut.
  10. Drive the vehicle at between 75 and 120 km/h (47 and 75 mph) for at least 10 minutes [B].

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

  11. Move the shift lever in B [C].
  12. Accelerate the vehicle to 75 km/h (47 mph) or more by depressing the accelerator pedal for at least 10 seconds [D].
  13. Soon after performing step [D] above, release the accelerator pedal for at least 8 seconds without depressing the brake pedal in order to execute fuel-cut control [E].

    HINT:
    Fuel-cut is performed when the following conditions are met:
    1. Accelerator pedal is fully released.
    2. Engine speed is 2500 rpm 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).
  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 DTC [F].

    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. 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 or P2196.
  20. Check the DTC judgment result.

    Tester Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    UNKNOWN
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT:
    1. If the judgment result shows ABNORMAL, the system has a malfunction.
    2. If the judgment result shows NORMAL, the system is normal.
    3. If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [B] through [E].


INSPECTION PROCEDURE

HINT:
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. Turn the power switch on (IG) and turn the tester on.
  3. Put the engine in inspection mode (Click here).
  4. Start the engine.
  5. Turn the tester on.
  6. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
  7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
  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) displayed on the tester.

HINT:
  1. 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%.
  1. Each sensor reacts in accordance with increases in the fuel injection volume.


Tester Display
(Sensor)
Injection Volume
Status
Voltage
AFS Voltage B1S1
(Air fuel ratio)
+25%
Rich
Less than 3.1 V
AFS Voltage B1S1
(Air fuel ratio)
-12.5%
Lean
More than 3.4 V
O2S B1S2
(Heated oxygen)
+25%
Rich
 More than 0.55 V
O2S B1S2
(Heated oxygen)
-12.5%
Lean
Less than 0.4 V

NOTICE:
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
A162605E12
A162598E12
-
2
A162596E06
A162598E12
  1. Air fuel ratio sensor
  2. Air fuel ratio sensor heater
  3. Air fuel ratio sensor circuit
3
A162605E12
A162596E07
  1. Heated oxygen sensor
  2. Heated oxygen sensor heater
  3. Heated oxygen sensor circuit
  4. Exhaust gas leaks
4
A162596E06
A162596E06
  1. Fuel pressure
  2. Exhaust gas leaks
    (Air fuel ratio extremely lean or rich)
  1. Following the Control the Injection Volume for A/F Sensor procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
  2. To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS Voltage B1S1.

HINT:
  1. Although the DTC titles say oxygen sensor, these DTCs relate to the air fuel ratio sensor.
  2. Sensor 1 refers to the sensor mounted in front of the Three-way Catalytic Converter (TWC) and located near the engine assembly.
  3. 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.
  4. 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.
  5. 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.
  6. Sensor 1 refers to the sensor closest to the engine assembly.
  7. Sensor 2 refers to the sensor farthest away from the engine assembly.

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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

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

  1. Read the DTCs.

    Result:

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

    HINT:
    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
Go to step 4
YES


3.PERFORM CONFIRMATION DRIVING PATTERN

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs (Click here).

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

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

  1. Put the engine in inspection mode (Click here).

  1. Start the engine and warm it up.

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

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

  1. Input the DTC: P2195 or P2196.

  1. Check the DTC judgment result.

    Result:

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



B
Go to step 4
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.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs (Click here).

  1. Put the engine in inspection mode (Click here).

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

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

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

    Result:

    Result
    		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
Go to step 15
A


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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Put the engine in inspection mode (Click here).

  1. Start the engine.

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

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

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

  1. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S) displayed on the tester.

    HINT:
    1. Change the fuel injection volume within the range of -12.0% to +12.0%. The injection volume can be changed in fine gradations.
    2. 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.
    3. If there is almost no response from the air fuel ratio sensor, a malfunction of the air fuel ratio sensor is suspected


    Tester Display (Sensor)
    		Injection Volume
    		Status
    		Voltage
    AFS Voltage B1S1
    (Air fuel ratio)
    		+12.0%
    		Rich
    		Below 3.1 V
    AFS Voltage B1S1
    (Air fuel ratio)
    		-12.0%
    		Lean
    		Higher than 3.4 V
    O2S B1S2
    (Heated oxygen)
    		+12.0%
    		Rich
    		Higher than 0.55 V
    O2S B1S2
    (Heated oxygen)
    		-12.0%
    		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
    		Misfire
    		Suspected Trouble Area
    		Proceed to
    Lean
    		Lean
    		Actual air fuel ratio lean
    		May occur
    1. PCV valve and hose
    2. PCV hose connections
    3. Fuel injector assembly blockage
    4. Gas leaks from exhaust system
    5. Intake system
    6. Fuel pressure
    7. Mass air flow meter sub-assembly
    8. Manifold absolute pressure sensor
    9. Engine coolant temperature sensor
    10. EGR valve assembly
    		A
    Rich
    		Rich
    		Actual air fuel ratio rich
    		-
    1. Fuel injector assembly leakage or blockage
    2. Gas leaks from exhaust system
    3. Ignition system
    4. Fuel pressure
    5. Mass air flow meter sub-assembly
    6. Manifold absolute pressure sensor
    7. 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.

HINT:
Refer to "Data List / Active Test" [AFS Voltage B1S1 and O2S B1S2] (Click here).



B
Go to step 16

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 from the 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
Go to step 18
OK


9.INSPECT FUEL INJECTOR ASSEMBLY

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



NG
REPLACE FUEL INJECTOR ASSEMBLY (Click here)
OK


10.REPLACE AIR FUEL RATIO SENSOR NO.2

  1. Replace the air fuel ratio sensor (Click here).


NEXT


11.PERFORM CONFIRMATION DRIVING PATTERN

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs (Click here).

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

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

  1. Put the engine in inspection mode (Click here).

  1. Start the engine and warm it up.

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

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

  1. Input the DTC: P2195 or P2196.

  1. 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


12.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Put the engine in inspection mode (Click here).

  1. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or more.

    HINT:
    The A/C switch and all accessory switches should be off.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.

  1. Confirm the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.

    HINT:
    1. Do not leave the EGR valve open for 10 seconds or more during the Active Test.
    2. Be sure to return the EGR valve to step 0 when the Active Test is completed.
    3. Do not open the EGR valve 30 steps or more during the Active Test.

    OK:
    MAP and idling condition change in response to EGR step position when Throttle Idle Position is ON in Data List.


    Standard:

    -
    		EGR Step Position (Active Test)
    0 Steps
    		0 to 30 Steps
    Idling condition
    		Steady idling
    		Idling changes from steady to rough idling
    MAP
    (Data List)
    		MAP value is 20 to 40 kPa (150 to 300 mmHg)
    (EGR valve is fully closed)
    		MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

    HINT:
    During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve.



OK
Go to step 14

NG
Go to step 13

13.INSPECT EGR VALVE ASSEMBLY

  1. Remove the EGR valve assembly (Click here).

  1. Check if the EGR valve is stuck open.

    OK:
    EGR valve is tightly closed.

  1. Reinstall the EGR valve assembly (Click here).



NG
REPLACE EGR VALVE ASSEMBLY (Click here)
OK


14.REPLACE ECM

  1. Replace the ECM (Click here).


NEXT


15.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs (Click here).

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

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

  1. Put the engine in inspection mode (Click here).

  1. Start the engine and warm it up.

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

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

  1. Input the DTC: P2195 or P2196.

  1. Check the DTC judgment result.

    Result 
    Tester Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    UNKNOWN
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit


NEXT

END 

16.REPLACE AIR FUEL RATIO SENSOR NO.2

  1. Replace the air fuel ratio sensor (Click here).


NEXT


17.PERFORM CONFIRMATION DRIVING PATTERN

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs (Click here).

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

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

  1. Put the engine in inspection mode (Click here).

  1. Start the engine and warm it up.

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

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

  1. Input the DTC: P2195 or P2196.

  1. Check the DTC judgment result.

    Result:

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



B
REPLACE ECM (Click here)
A

END 

18.CHECK FUEL LINE

  1. Check the fuel lines for leaks or blockage.



NG
REPAIR OR REPLACE FUEL LINE
OK

REPLACE FUEL PUMP