| 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.
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 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 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.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| P2195 P2197 |
Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)
|
|
| While fuel cut operation performed (during vehicle deceleration), air fuel ratio sensor current 2.1 mA or more for 3 seconds (2 trip detection logic) |
|
|
| P2196 P2198 |
Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)
|
|
| While fuel cut operation performed (during vehicle deceleration), air fuel ratio sensor current less than 0.23 mA for 3 seconds or more (2 trip detection logic) |
|
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.
When any of these DTCs are set, check the air fuel ratio sensor voltage output by entering the following menus: Powertrain / Engine and ECT / Data List / AFS Voltage B1S1 or AFS Voltage B2S1.
Short-term fuel trim values can also be read using the GTS.
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 GTS.
If an air fuel ratio sensor malfunction is detected, the ECM sets a DTC.
MONITOR DESCRIPTION
Sensor Voltage Detection Monitor:Under air fuel ratio feedback control, If the air fuel ratio sensor output voltage is less than 2.8 V (very rich condition) for 5 seconds despite the heated oxygen sensor output voltage being less than 0.59 V, the ECM stores DTC P2196 or P2198. Alternatively, if the air fuel ratio sensor output voltage is higher than 3.8 V (very lean condition) for 5 seconds despite the heated oxygen sensor output voltage being 0.21 V or higher, DTC P2195 or P2197 is stored.
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 2.1 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 stores DTC P2195 or P2197 (stuck on high side). If the air fuel ratio sensor output is less than 0.23 mA for more than 3 seconds of cumulative time, the ECM stores DTC P2196 or P2198 (stuck on low side).
MONITOR STRATEGY
| Required Sensors/Components (Main) | Air fuel ratio sensor |
| Required Sensors/Components (Related) | Heated oxygen sensor |
| Frequency of Operation | Continuous: Sensor voltage detection monitor Once per driving cycle: Sensor current detection monitor |
| Duration | 5 seconds: Sensor voltage detection monitor 3 seconds: Sensor current detection monitor |
TYPICAL ENABLING CONDITIONS
| Time after engine start | 30 seconds or more |
| Fuel system status | Closed loop |
| Battery voltage | 11 V or more |
| Engine coolant temperature | 75°C (167°F) or more |
| Atmospheric pressure | 76 kPa(abs) [570 mmHg(abs)] or more |
| Air fuel ratio sensor status | Activated |
| Continuous time of fuel cut | 4 seconds or more, and less than 10 seconds |
TYPICAL MALFUNCTION THRESHOLDS
| Heated oxygen sensor voltage | 0.21 V or more |
| Air fuel ratio sensor voltage | More than 3.8 V |
| Heated oxygen sensor voltage | Less than 0.59 V |
| Air fuel ratio sensor voltage | Less than 2.8 V |
| Air fuel ratio sensor current | 2.1 mA or more |
| Air fuel ratio sensor current | Less than 0.23 mA |
CONFIRMATION DRIVING PATTERN
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Click here.
Turn the engine switch off and wait for at least 30 seconds.
Turn the engine switch on (IG) and turn the GTS on.
Start the engine, and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [A].
On the GTS, enter the following menus to check the fuel-cut status: Powertrain / Engine and ECT / Data List / Idle Fuel Cut.
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.
With the shift lever in M [C], 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.
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].
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 1400 rpm).
Allow the vehicle to decelerate until the vehicle speed decreases to less than 10 km/h (6 mph).
Repeat steps [C] through [E] above at least 3 times in one driving cycle.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
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.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P2195, P2196, P2197 or P2198.
Check the DTC judgment result.
| GTS Display | Description |
|---|---|
| NORMAL |
|
| ABNORMAL |
|
| INCOMPLETE |
|
| N/A |
|
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 N/A, perform steps [B] through [F] again.
WIRING DIAGRAM
INSPECTION PROCEDURE
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 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 GTS. 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.
PROCEDURE
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2195, P2196, P2197 OR P2198)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTCs.
| Result | ||||||||
|---|---|---|---|---|---|---|---|---|
|
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 |
|
CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST
Has the vehicle run out of fuel in the past?
| NO |
|
READ VALUE USING GTS (TEST VALUE OF A/F SENSOR) Click here |
| YES |
|
PERFORM CONFIRMATION DRIVING PATTERN (DTC P2195, P2196, P2197 OR P2198)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Clear the DTCs Click here.
Turn the engine switch off and wait for 30 seconds.
Turn the engine switch on (IG) and turn the GTS on.
Start the engine and warm it up.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P2195, P2196, P2197 or P2198.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
READ VALUE USING GTS (TEST VALUE OF A/F SENSOR) Click here |
| A |
|
DTC CAUSED BY RUNNING OUT OF FUEL
READ VALUE USING GTS (TEST VALUE OF A/F SENSOR)
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Clear DTCs.
Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Data List / AFS Current B1S1 and AFS Current B2S1.
Check the test value of the A/F sensor output current during fuel-cut.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
REPLACE AIR FUEL RATIO SENSOR Click here |
| A |
|
READ VALUE USING GTS (OUTPUT VOLTAGE OF A/F SENSOR)
Connect the GTS to the DLC3.
Start the engine.
Turn the GTS on.
Warm up the air fuel ratio sensor at an engine speed of 2500 rpm for 90 seconds.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / AFS Voltage B1S1 or AFS Voltage B2S1.
Perform the Control the Injection Volume for A/F Sensor operation with the engine idling.
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 GTS.
Tech Tips
Change the fuel injection volume within the range of -12.5% to +12.5%.
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.
| GTS Display (Sensor) | Injection Volume | Status | Voltage |
|---|---|---|---|
| AFS Voltage B1S1 or AFS Voltage B2S1 (Air fuel ratio) |
+12.5% | Rich | Below 3.1 V |
| -12.5% | Lean | Higher than 3.4 V | |
| O2S B1S2 or O2S B2S2 (Heated oxygen) |
+12.5% | Rich | Higher than 0.55 V |
| -12.5% | Lean | Below 0.4 V |
| 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 | B |
Lean: During the Control the Injection Volume for A/F Sensor 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 for A/F Sensor 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 for A/F Sensor 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 |
|
CHECK INTAKE SYSTEM
Check the air induction system for vacuum leaks.
| OK |
|---|
| No leaks in system. |
Tech Tips
Perform "Inspection After Repair" after replacing the air induction system Click here.
| NG |
|
REPAIR OR REPLACE INTAKE SYSTEM |
| OK |
|
CHECK FOR EXHAUST GAS LEAK
Check for exhaust gas leaks.
| OK |
|---|
| No gas leaks. |
| NG |
|
REPAIR OR REPLACE EXHAUST SYSTEM |
| OK |
|
CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
Check the fuel pressure Click here.
| NG |
|
CHECK FUEL LINE Click here |
| OK |
|
INSPECT FUEL INJECTOR FOR PORT INJECTION
Check the injector injection (for port injection) (whether fuel volume is high or low, and whether injection pattern is poor) Click here.
Tech Tips
Perform "Inspection After Repair" after replacing the fuel injector assembly (for port injection) Click here.
| NG |
|
REPLACE FUEL INJECTOR FOR PORT INJECTION Click here |
| OK |
|
CHECK FUEL PRESSURE (HIGH PRESSURE SIDE)
Check the fuel pressure (high pressure side) Click here.
| NG |
|
REPAIR OR REPLACE FUEL SYSTEM (HIGH PRESSURE SIDE) |
| OK |
|
INSPECT FUEL INJECTOR FOR DIRECT INJECTION
Inspect the fuel injector for direct injection Click here.
Tech Tips
Perform "Inspection After Repair" after replacing the fuel injector assembly (for direct injection) Click here.
| NG |
|
REPLACE FUEL INJECTOR FOR DIRECT INJECTION Click here |
| OK |
|
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
Tech Tips
Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Clear the DTCs Click here.
Turn the engine switch off and wait for at least 30 seconds.
Turn the engine switch on (IG) and turn the GTS on.
Start the engine and warm it up.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P2195, P2196, P2197 or P2198.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
END |
| A |
|
REPLACE ECM
Replace the ECM Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Clear the DTC Click here.
Turn the engine switch off and wait for at least 30 seconds.
Turn the engine switch on (IG) and turn the GTS on.
Start the engine and warm it up.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P2195, P2196, P2197 or P2198.
Check the DTC judgment result.
| GTS Display | Description |
|---|---|
| NORMAL |
|
| ABNORMAL |
|
| INCOMPLETE |
|
| N/A |
|
| NEXT |
|
END
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
Tech Tips
Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Clear the DTCs Click here.
Turn the engine switch off and wait for at least 30 seconds.
Turn the engine switch on (IG) and turn the GTS on.
Start the engine and warm it up.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P2195, P2196, P2197 or P2198.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
REPLACE ECM Click here |
| A |
|
END
CHECK FUEL LINE
Check the fuel lines for leaks or blockage.
Tech Tips
Perform "Inspection After Repair" after replacing the fuel pump Click here.
| NG |
|
REPAIR OR REPLACE FUEL LINE |
| OK |
|
REPLACE FUEL PUMP Click here