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

Engine Hybrid System. Yaris. Ncp93, 131
1Nz-Fe Engine Control. Yaris. Ncp93, 131

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

MONITOR RESULT

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

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

CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST

CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)

READ VALUE USING TECHSTREAM (TEST VALUE OF AIR FUEL RATIO SENSOR)

READ VALUE USING TECHSTREAM (OUTPUT VOLTAGE OF AIR FUEL RATIO SENSOR)

CHECK INTAKE SYSTEM

CHECK EXHAUST GAS LEAK

CHECK FUEL PRESSURE

INSPECT FUEL INJECTOR ASSEMBLY

REPLACE AIR FUEL RATIO SENSOR

CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)

REPLACE ECM

CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)

REPLACE AIR FUEL RATIO SENSOR

CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)

CHECK FUEL LINE

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)


DESCRIPTION

HINT:
  1. Although the DTC titles say oxygen sensor, these DTCs relate to the Air-Fuel Ratio (A/F) sensor.
  2. Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and located near the engine assembly.
The A/F 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 A/F sensor malfunctions, the ECM is unable to control the air-fuel ratio accurately.
The A/F sensor is of 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 air-fuel ratio 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, and 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 A/F sensor is the current output element, a current is converted into a voltage inside the ECM. Any measurements taken at the A/F sensor or ECM connectors will show a constant voltage.

Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)


DTC No.
DTC Detection Condition
Trouble Area
P2195
Conditions (a) and (b) continue for 10 seconds or more
(2 trip detection logic):
(a) A/F sensor voltage more than 3.8 V
(b) Heated Oxygen (HO2) sensor voltage 0.15 V or more
  1. Open or short in A/F sensor (sensor 1) circuit
  2. A/F sensor (sensor 1)
  3. Intake system
  4. Fuel pressure
  5. Fuel injector assembly
  6. ECM
While fuel cut operation performed (during vehicle deceleration), A/F sensor current 3.6 mA or more for 3 seconds (2 trip detection logic)
  1. A/F sensor
  2. ECM
P2196
Conditions (a) and (b) continue for 10 seconds or more
(2 trip detection logic):
(a) A/F sensor voltage less than 2.8 V for 10 seconds
(b) HO2 sensor voltage less than 0.6 V
  1. Open or short in A/F sensor (sensor 1) circuit
  2. A/F sensor (sensor 1)
  3. Intake system
  4. Fuel pressure
  5. Fuel injector assembly
  6. ECM
While fuel cut operation performed (during vehicle deceleration), A/F sensor current less than 1.0 mA for 3 seconds (2 trip detection logic)
  1. A/F sensor
  2. ECM
HINT:
  1. When either of these DTCs is stored, check the A/F sensor output by entering the following menus on a Techstream: Powertrain / Engine and ECT / Data List / AFS Voltage B1S1.
  2. Short-term fuel trim values can also be read using the Techstream.
  3. The ECM regulates the voltages at the A1A+ and A1A- terminals of the ECM to a constant level. Therefore, the A/F sensor output voltage cannot be confirmed without using the Techstream.
  4. If the A/F sensor is malfunctioning, the ECM stores the DTC P2195 or P2196.

MONITOR DESCRIPTION

  1. Sensor voltage detection monitor
    Under the air-fuel ratio feedback control, if the A/F sensor output voltage indicates rich or lean for a certain period of time, the ECM determines that there is a malfunction in the A/F sensor. The ECM illuminates the MIL and stores a DTC.
    Example:
    If the A/F sensor output voltage is less than 2.8 V (very rich condition) for 10 seconds, despite the rear HO2 sensor output voltage being less than 0.6 V, the ECM stores DTC P2196. Alternatively, if the A/F sensor output voltage is more than 3.8 V (very lean condition) for 10 seconds, despite the rear HO2 sensor output voltage being 0.15 V or more, DTC P2195 is stored.
  1. Sensor current detection monitor
    A rich air-fuel mixture causes a low A/F sensor current, and a lean air-fuel mixture causes a high A/F 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 A/F sensor current during fuel cut and detects any abnormal current values.
    If the A/F sensor output is 3.6 mA or more for 3 seconds or more of cumulative time, the ECM interprets this as a malfunction in the A/F sensor and stores DTC P2195 (high-side stuck). If the A/F sensor output is less than 1.0 mA for 3 seconds or more of cumulative time, the ECM stores DTC P2196 (low-side stuck).

Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)


MONITOR STRATEGY


Related DTCs
P2195: A/F sensor signal stuck lean
P2196: A/F sensor signal stuck rich
Required Sensors/Components (Main)
A/F sensor
Required Sensors/Components (Related)
HO2 sensor
Frequency of Operation
Continuous
Duration
10 seconds: Sensor voltage detection monitor
3 seconds: Sensor current detection monitor
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


All
Monitor runs whenever following DTCs not present
P0016 (VVT system- misalignment)
P0031, P0032 (A/F sensor heater)
P0100, P0102, P0103 (MAF meter)
P0110, P0112, P0113 (IAT sensor)
P0115, P0117, P0118 (ECT sensor)
P0120 - P0123, P0220, P0222, P0223, P2135 (TP sensor)
P0125 (Insufficient ECT for Closed Loop)
P0128 (Thermostat)
P0171, P0172 (Fuel system)
P0301 - P0304 (Misfire)
P0335 (CKP sensor)
P0340 (CMP sensor)
P0450 - P0453 (EVAP system)
P0500 (VSS)
P0505 (ISC)
P0722 (VSS)

Sensor voltage detection monitor (Lean side malfunction P2195):
Duration while all of following conditions met
2 seconds or more
Rear oxygen sensor voltage
0.15 V or more
Time after engine start
30 seconds or more
A/F sensor status
Activated
Fuel system status
Closed-loop
Engine
Running

Sensor voltage detection monitor (Rich side malfunction P2196):
Duration while all of following conditions met
2 seconds or more
Rear oxygen sensor voltage
Below 0.6 V
Time after engine start
30 seconds or more
A/F sensor status
Activated
Fuel system status
Closed-loop
Engine
Running

Sensor current detection monitor P2195 and P2196
Battery voltage
11 V or more
Atmospheric pressure
76 kPa (570 mmHg) or more
A/F sensor status
Activated
Continuous time of fuel cut
3 to 10 seconds
ECT
75°C (167°F) or more

TYPICAL MALFUNCTION THRESHOLDS


Sensor voltage detection monitor (Lean side malfunction P2195):
A/F sensor voltage
More than 3.8 V for 10 seconds

Sensor voltage detection monitor (Rich side malfunction P2196):
A/F sensor voltage
Less than 2.8 V for 10 seconds

Sensor current detection monitor (High side malfunction P2195):
A/F sensor current during fuel cut
3.6 mA or more

Sensor current detection monitor (Rich side malfunction P2196):
A/F sensor current during fuel cut
Less than 1.0 mA

MONITOR RESULT

Refer to Checking Monitor Status (YARIS_NCP93 RM000000PDR0A3X.html).

CONFIRMATION DRIVING PATTERN


Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)


Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON.
  3. Turn the Techstream 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 Techstream on.
  7. Start the engine, and warm it up until the ECT reaches 75°C (167°F) or higher [A].
  8. On the Techstream, enter the following menus to check the fuel-cut status: Powertrain / Engine and ECT / Data List / Idle Fuel Cut.
  9. Drive the vehicle at between 60 and 120 km/h (38 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 64 km/h (40 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 4 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).
  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 and ECT / Trouble Codes [F].
  16. Read pending DTCs.
    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  17. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  18. Input the DTC: P2195 or P2196.
  19. Check the DTC judgment result.

    Techstream 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
    N/A
    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 NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, perform steps [B] through [F] again.
  20. If no pending DTC is output, perform a universal trip and check for permanent DTCs (YARIS_NCP93 RM000000PDK0QGX.html).
    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM


Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P2195 Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
  1. 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 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.
  2. 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.
  3. 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.
  4. Sensor 1 refers to the sensor closest to the engine assembly.
  5. 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 Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read 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 (YARIS_NCP93 RM000000PDF0E6X.html)
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.CHECK WHETHER DTC OUTPUT RECURS (DTC P2195 OR P2196)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear DTCs (YARIS_NCP93 RM000000PDK0QGX.html).

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

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in 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
    		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 TECHSTREAM (TEST VALUE OF AIR FUEL RATIO SENSOR)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear DTCs (YARIS_NCP93 RM000000PDK0QGX.html).

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

  1. Enter the following menus: Powertrain / Engine and ECT / Monitor / Current Monitor / O2 Sensor / Current.

  1. Check that the status of O2 Sensor is Complete. If the status is still Incomplete, drive the vehicle according to the driving pattern again.

  1. Enter the following menus: Powertrain / Engine and ECT / Monitor / O2 Sensor / Details / RANGE B1S1.

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

    Result
    Result
    		Proceed to
    Within normal range (1.0 mA or higher, and below 3.6 mA)
    		A
    Outside normal range (Below 1.0 mA, or 3.6 mA or higher)
    		B


B
Go to step 14
A


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

  1. Connect the Techstream to the DLC3.

  1. Start the engine.

  1. Turn the Techstream on.

  1. Warm up the engine and run the engine at an engine speed of 2500 rpm for approximately 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 (press the RIGHT or LEFT button to change the fuel injection volume).

  1. Monitor the voltage outputs of the air fuel ratio sensor and the heated oxygen sensor (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.

    HINT:
    1. Change the fuel injection volume within the range of -12% to +12%. 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 the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

    Standard:

    Techstream Display (Sensor)
    		Injection Volume
    		Status
    		Voltage
    AFS Voltage B1S1
    (Air fuel ratio)
    		+12%
    		Rich
    		Below 3.1 V
    -12%
    		Lean
    		Higher than 3.4 V
    O2S B1S2
    (Heated oxygen)
    		+12%
    		Rich
    		Higher than 0.55 V
    -12%
    		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 Control the Injection Volume Active Test, the air fuel ratio sensor output voltage (AFS Voltage B1S1) is consistently higher than 3.4 V, and the HO2 sensor output voltage (O2S B1S2) is consistently below 0.4 V.
    Rich: During Control the Injection Volume Active Test, the AFS Voltage B1S1 is consistently below 3.1 V, and the O2S B1S2 is consistently higher than 0.55 V.
    Lean/Rich: During Control the Injection Volume Active Test, the output voltage of the HO2 sensor alternates correctly.
    HINT:
    Refer to "Data List / Active Test" [AFS Voltage B1S1 and O2S B1S2] (YARIS_NCP93 RM000000PDN0J9X.html).


B
Go to step 14
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.CHECK EXHAUST GAS LEAK

  1. Check the exhaust gas leaks.

    OK:
    No exhaust gas leaks.


NG
REPAIR OR REPLACE EXHAUST SYSTEM
OK


8.CHECK FUEL PRESSURE

  1. Check the fuel pressure (YARIS_NCP93 RM000001EF100YX_01_0002.html).



NG
Go to step 16
OK


9.INSPECT FUEL INJECTOR ASSEMBLY

  1. Check the fuel injector injection (whether fuel volume is high or low, and whether injection pattern is poor) (YARIS_NCP93 RM000001EDQ046X.html).



NG
REPLACE FUEL INJECTOR ASSEMBLY (YARIS_NCP93 RM000001EDS04FX.html)
OK


10.REPLACE AIR FUEL RATIO SENSOR

  1. Replace the air fuel ratio sensor (YARIS_NCP93 RM000001CKA00YX.html).


NEXT


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

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear DTCs (YARIS_NCP93 RM000000PDK0QGX.html).

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

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in 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
    		Proceed to
    ABNORMAL (DTC P2195 or P2196 is output)
    		A
    NORMAL (DTC is not output)
    		B


B
END
A


12.REPLACE ECM

  1. Replace the ECM (YARIS_NCP93 RM000001CN002AX.html).


NEXT


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

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear DTCs (YARIS_NCP93 RM000000PDK0QGX.html).

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

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in 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
    Techstream 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
    N/A
    1. Unable to perform DTC judgment
    2. 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 (YARIS_NCP93 RM000001CKA00YX.html).


NEXT


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

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear DTCs (YARIS_NCP93 RM000000PDK0QGX.html).

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

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in 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
    		Proceed to
    NORMAL (DTC is not output)
    		A
    ABNORMAL (DTC P2195 or P2196 is output)
    		B


B
REPLACE ECM (YARIS_NCP93 RM000001CN002AX.html)
A

END

16.CHECK FUEL LINE

  1. Check the fuel lines for leaks or blockage.



NG
REPAIR OR REPLACE FUEL SYSTEM
OK

REPLACE FUEL PUMP (YARIS_NCP93 RM000001JUN00MX.html)