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)

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

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

for Preparation Click here


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 voltage* that corresponds to the actual air-fuel ratio. This sensor voltage is used to provide the ECM (Included in HV Control ECU) 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 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 though 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 A/F sensor is the current output element, a current is converted to a voltage inside the ECM. Any measurements taken at the A/F sensor or ECM connectors will show a constant voltage.

A107164E03


DTC No.
DTC Detection Condition
Trouble Area
P2195
P2197
  1. Conditions (a) and (b) continue for 2 seconds or more
    (2 trip detection logic):
    1. Air-Fuel Ratio (A/F) sensor voltage more than 3.8 V
    2. Heated Oxygen (HO2) sensor voltage 0.15 V or more
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. A/F sensor (bank 1, 2 sensor 1) heater
  4. A/F HTR relay
  5. A/F sensor heater and relay circuits
  6. Air induction system
  7. Fuel pressure
  8. Injector
  9. HV Control ECU
P2196
P2198
  1. Conditions (a) and (b) continue for 2 seconds or more
    (2 trip detection logic):
    1. A/F sensor voltage less than 2.8 V
    2. HO2 sensor voltage less than 0.85 V
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. A/F sensor (bank 1, 2 sensor 1) heater
  4. A/F HTR relay
  5. A/F sensor heater and relay circuits
  6. Air induction system
  7. Fuel pressure
  8. Injector
  9. HV Control ECU

HINT:
  1. DTCs P2195 and P2196 indicate malfunctions related to bank 1 A/F sensor circuit.
  2. DTCs P2197 and P2198 indicate malfunctions related to bank 2 A/F sensor circuit.
  3. Bank 1 refers to the bank that includes cylinder No. 1.
  4. Bank 2 refers to the bank that includes cylinder No. 2.
  5. When any of these DTCs are set, check the A/F sensor output voltage by entering the following menus on the intelligent tester: Powertrain / Engine / Data List / AFS B1S1, AFS B2S1.
  6. Short-term fuel trim values can also be read using an intelligent tester.
  7. The ECM (Included in HV Control ECU) regulates the voltages at the A1A+, A2A+, A1A- and A2A- terminals of the ECM to a constant level. Therefore, the A/F sensor output voltage cannot be confirmed without using the intelligent tester.
  8. If a A/F sensor malfunction is detected, the ECM sets a DTC.


WIRING DIAGRAM


A110945E03


CONFIRMATION DRIVING PATTERN


A079199E28

  1. Connect an intelligent tester to the DLC3.
  2. Switch the ECM from normal mode to check mode using the intelligent tester (Click here).
  3. Put the engine in inspection mode (Click here).
  4. Start the engine and warm it up with all the accessory switches OFF.
  5. Deactivate the inspection mode and drive the vehicle at 47 to 75 mph (75 to 120 km/h) for 5 to 10 minutes (the engine must be run during monitoring).

    HINT:
    If malfunction exists, the MIL will be illuminated during step (d).

    NOTICE:
    1. If the conditions in this test are not strictly followed, no malfunction will be detected. If you do not have the intelligent tester, turn the power switch OFF after performing steps 4 and 5, then perform step 4 and 5 again.
    2. Do not drive the vehicle without deactivating inspection mode, otherwise damaging the transaxle may result.


INSPECTION PROCEDURE

HINT:
Malfunctioning areas can be identified by performing the A/F Control function provided in theActive Test. The A/F Control function can help to determine whether the Air-fuel Ratio (A/F) sensor, Heated Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the A/F Control operation using the intelligent tester.
  1. Connect the intelligent tester to the DLC3.
  2. Put the engine in inspection mode (Click here).
  3. Start the engine and turn the tester ON.
  4. Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
  5. On the intelligent tester, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor.
  6. Perform the A/F Control operation with the engine in an idling condition (press the Right or Left button to change the fuel injection volume).
  7. Monitor the output voltages of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2) displayed on the tester.

HINT:
  1. The A/F Control 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.


Standard:

Tester Display
(Sensor)
Injection Volume
Status
Voltage
AFS B1S1 or AFS B2S1
(A/F)
+25 %
Rich
Less than 3.0
AFS B1S1 or AFS B2S1
(A/F)
-12.5 %
Lean
More than 3.35
O2S B1S2 or O2S B2S2
(HO2)
+25 %
Rich
 More than 0.55
O2S B1S2 or O2S B2S2
(HO2)
-12.5 %
Lean
Less than 0.4

NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the HO2S (sensor 2) output has a maximum of 20 seconds of delay.


Case
A/F Sensor (Sensor 1)
Output Voltage
HO2 Sensor (Sensor 2)
Output Voltage
Main Suspected Trouble Areas
1
Injection Volume
+25 %
-12.5 %
A103184
Injection Volume
+25 %
-12.5 %
A103184
-
Output Voltage
More than 3.35 V
Less than 3.0 V
A107708
Output Voltage
More than 0.55 V
Less than 0.4 V
A103186
2
Injection Volume
+25 %
-12.5 %
A103184
Injection Volume
+25 %
-12.5 %
A103184
  1. A/F sensor
  2. A/F sensor heater
    A/F sensor circuit
Output Voltage
Almost
no reaction
A103185
Output Voltage
More than 0.55 V
Less than 0.4 V
A103186
3
Injection Volume
+25 %
-12.5 %
A103184
Injection Volume
+25 %
-12.5 %
A103184
  1. HO2 sensor
  2. HO2 sensor heater
  3. HO2 sensor circuit
Output Voltage
More than 3.35 V
Less than 3.0 V
A107708
Output Voltage
Almost
no reaction
A103185
4
Injection volume
+25 %
-12.5 %
A103184
Injection Volume
+25 %
-12.5 %
A103184
  1. Injector
  2. Fuel pressure
  3. Gas leakage from exhaust system
    (Air-fuel ratio extremely lean or rich)
Output Voltage
Almost
no reaction
A103185
Output Voltage
Almost
no reaction
A103185
Following the A/F Control procedure enables technicians to check and graph the voltage outputs of both the A/F and HO2 sensors.

HINT:
  1. 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 running or stopped, 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 A/F 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 A/F sensor voltage could be caused by a lean air-fuel mixture. Check for conditions that would cause the engine to run lean.

1.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO P2195, P2196, 2197 OR P2198)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON.

  1. Turn the tester ON.

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

  1. Read DTCs.

    Result:

    Display (DTC Output)
    		Proceed to
    P2195, P2196, P2197, or P2198
    		A
    P2195, P2196, P2197, or P2198 and other DTCs
    		B

    HINT:
    If any DTCs other than P2195, P2196, P2197 or P2198 are output, troubleshoot those DTCs first.



B
GO TO DTC CHART
A


2.READ VALUE USING INTELLIGENT TESTER (OUTPUT VOLTAGE OF A/F SENSOR)

  1. Connect the intelligent tester to the DLC3.

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

  1. Start the engine.

  1. Turn the tester ON.

  1. Warm up the Air-Fuel Ratio (A/F) sensor at an engine speed of 2,500 rpm for 90 seconds.

  1. On the tester, enter the following menus: Powertrain / Engine / Active Test / Custom List / AFS B1S1 or AFS B2S1 and Engine Speed / Record.



  1. Check the A/F sensor voltage three times, when the engine is in each of the following conditions:

    1. While idling (check for at least 30 seconds)

    2. At an engine speed of approximately 2,500 rpm (without any sudden changes in engine speed)



    3. Raise the engine speed to 4,000 rpm and then quickly release the accelerator pedal so that the throttle valve is fully closed.

      Standard voltage:

      Condition
      		A/F Sensor Voltage Variation
      		Reference
      (1) and (2)
      		Changes at approximately 3.3 V
      		Between 3.1 V and 3.5 V
      (3)
      		Increases to 3.8 V or more
      		This occurs during engine deceleration
      (when fuel-cut performed)


      A107161E01

      HINT:
      1. For more information, see the diagrams below.
      2. If the output voltage of the A/F sensor remains at approximately 3.3 V (see Malfunction Condition diagram) under any conditions, including those above, the A/F sensor may have an open circuit. (this will also happen if the A/F sensor heater has an open circuit.)
      3. If the output voltage of the A/F sensor remains at either approximately 3.8 V or more, or 2.8 v or less (see Malfunction Condition diagram) under any conditions, including those above, the A/F sensor may have a short circuit.
      4. The ECM (Included in HV Control ECU) stops fuel injection (fuel cut) during engine deceleration. This causes a lean condition and result in a momentary increase in the A/F sensor output voltage.
      5. The ECM must establish a closed throttle valve position learning value to perform fuel cut. If the battery terminal has been reconnected, the vehicle must be driven over 10 mph (16 km/h) to allow the ECM terminal has been reconnected, the vehicle must be driven over 10 mph (16 km/h) to allow the ECM to learn the closed throttle valve position.
      6. When the vehicle is driven:
        The output voltage of the A/F sensor may be below 2.8 V during fuel enrichment. For the vehicle, this translates to a sudden increase in speed with the accelerator pedal fully depressed when trying to overtake another vehicle. The A/F sensor is functioning normally.
      7. The A/F sensor is a current output element; therefore, the current is converted into a voltage inside the ECM. Measuring the voltage at the connectors of the A/F sensor or ECM will show a constant voltage result.



NG
Go to step 13
OK


3.INSPECT AIR FUEL RATIO SENSOR


    A052607E13

  1. Disconnect the A4 or A5 A/F sensor connector.

  1. Measure the resistance between the terminals of the A/F sensor connector.

    Standard resistance:
    Tester Connection
    		Specified Condition
    HA1A, HA2A (1) - +B (2)
    		1.8 Ω to 3.4 Ω at 20°C (68°F)
    HA1A, HA2A (1) - +B (2)
    		10 kΩ or higher

  1. Reconnect the A/F sensor connector.



NG
REPLACE AIR FUEL RATIO SENSOR
OK


4.INSPECT A/F RELAY


    B016200E02

  1. Remove the A/F relay from the engine room No. 2 relay block.

  1. Measure the A/F relay resistance.

    Standard resistance:
    Tester Connection
    		Specified Condition
    3 - 5
    		10 kΩ or higher
    3 - 5
    		Below 1 Ω
    (when battery voltage applied to terminals 1 and 2)

  1. Reinstall the A/F HTR relay.



NG
REPLACE A/F RELAY
OK


5.CHECK HARNESS AND CONNECTOR (A/F SENSOR - HV CONTROL ECU)


    A110913E03

  1. Disconnect the A4 and A5 A/F sensor connector.

  1. Turn the ignition switch ON.

  1. Measure the voltage between the +B terminal of the A/F sensor connector and body ground.

    Standard voltage:
    Tester Connection
    		Specified Condition
    +B (2) - Body ground
    		9 to 14 V

  1. Turn the ignition switch off.

  1. Disconnect the H33 HV Control ECU connector.

  1. Measure the resistance between the terminals of the A/F sensor and HV Control ECU.

    Standard resistance (Check for open):
    Tester Connection
    		Specified Condition
    HA1A ( A5-1) - HA1A (H33-4)
    		Below 1 Ω
    A1A+ (A5-3) - A1A+ (H33-22)
    		Below 1 Ω
    A1A- (A5-4) - A1A- (H33-30)
    		Below 1 Ω
    HA2A (A4-1) - HA2A (H33-3)
    		Below 1 Ω
    A2A+ (A4-3) - A2A+ (H33-23)
    		Below 1 Ω
    A2A- (A4-4) - A2A- (H33-31)
    		Below 1 Ω

    Standard resistance (Check for short):
    Tester Connection
    		Specified Condition
    HA1A ( A5-1) or HA1A (H33-4) - Body ground
    		10 kΩ or higher
    A1A+ (A5-3) or A1A+ (H33-22) - Body ground
    		10 kΩ or higher
    A1A- (A5-4) or A1A- (H33-30) - Body ground
    		10 kΩ or higher
    HA2A (A4-1) or HA2A (H33-3) - Body ground
    		10 kΩ or higher
    A2A+ (A4-3) or A2A+ (H33-23) - Body ground
    		10 kΩ or higher
    A2A- (A4-4) or A2A- (H33-31) - Body ground
    		10 kΩ or higher

  1. Reconnect the HV Control ECU connector.



  1. Reconnect the A/F sensor connector.


    A103833E10



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


6.CHECK AIR INDUCTION SYSTEM

  1. Check the air induction system for vacuum leakage.

    OK:
    No leakage from air induction system.



NG
REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK


7.CHECK FUEL PRESSURE

  1. Check the fuel pressure (Click here).

    Standard:
    304 to 343 kPa (3.1 to 3.5 kgf/cm2, 44.1 to 49.7 psi)



NG
REPAIR OR REPLACE FUEL SYSTEM
OK


8.INSPECT FUEL INJECTOR ASSEMBLY

  1. Check the injector injection (Click here).

    OK:
    13 cm3 (0.8 cu in.) or less



NG
REPLACE FUEL INJECTOR ASSEMBLY
OK


9.REPLACE AIR FUEL RATIO SENSOR

NEXT


10.PERFORM CONFIRMATION DRIVING PATTERN

NEXT


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

  1. Read DTCs using the intelligent tester.

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

    Result:

    Display (DTC Output)
    		Proceed to
    No output
    		A
    P2195, P2196, P2197 or P2198
    		B



B
REPLACE HV CONTROL ECU
A


12.CONFIRM WHETHER VEHICLE HAS RUN OUT OF FUEL IN PAST


NO
CHECK FOR INTERMITTENT PROBLEMS
YES

DTC CAUSED BY RUNNING OUT OF FUEL 

13.REPLACE AIR FUEL RATIO SENSOR

NEXT


14.PERFORM CONFIRMATION DRIVING PATTERN

NEXT


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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the tester ON.

  1. Read DTCs using the intelligent tester.

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

    Result:

    Display (DTC Output)
    		Proceed to
    No output
    		A
    P2195, P2196, P2197 or P2198 (A/F sensor pending DTCs)
    		B



B
REPLACE HV CONTROL ECU
A

END