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 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 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)
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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) |
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P2196 P2198 |
Conditions (a) and (b) continue for 5 seconds or more (2 trip detection logic)
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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) |
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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 / A/F Control System / AFS B1 S1 or AFS B2 S1.
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 a air fuel ratio sensor malfunction is detected, the ECM sets a DTC.
MONITOR DESCRIPTION
Sensor voltage detection monitorUnder 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 output voltage falls from 0.59 V or more to less than 0.21 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 heated oxygen sensor output voltage rises from less than 0.21 V to 0.59 V or more for 5 seconds, DTC P2195 or P2197 is set.
Sensor current detection monitorA 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).
WIRING DIAGRAM
CONFIRMATION DRIVING PATTERN
This confirmation driving pattern is used in the "Perform Confirmation Driving Pattern" procedure of the following diagnostic troubleshooting procedure.
(a) Connect the intelligent tester to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the tester ON.
(d) Clear the DTCs Click here.
(e) Start the engine, and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
(f) Enter the following menus to check the fuel-cut status: Powertrain / Engine / Data List / All Data / Idle Fuel Cut.
(g) Drive the vehicle at between 60 km/h and 120 km/h for at least 10 minutes.
(h) Move the shift lever to M.
(i) Change the transmission to 2nd gear.
(j) Drive the vehicle at proper vehicle speed to perform fuel-cut operation (refer to the following HINT).
Tech Tips
Fuel-cut is performed when the following conditions are met:
Accelerator pedal fully released.
Engine speed is 2500 rpm or more (fuel injection returns at 1000 rpm).
(k) Accelerate the vehicle to 64 km/h (40 mph) or more by depressing the accelerator pedal for at least 10 seconds.
(l) Soon after performing step (j) above, release the accelerator pedal for at least 4 seconds without depressing the brake pedal, in order to execute fuel-cut control.
(m) Allow the vehicle to decelerate until the vehicle speed declines to less than 10 km/h (6 mph).
(n) Repeat steps from (h) through (k) above at least 3 times in one driving cycle.
Tech Tips
Completion of all O2S (A/F) Monitor is required to change the value in Data List.
CAUTION:
Strictly observe posted speed limits, traffic laws, and road conditions when performing these drive patterns.
INSPECTION PROCEDURE
Tech Tips
Intelligent tester only:
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.
Connect the intelligent tester to the DLC3.
Start the engine and turn the tester ON.
Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
On the tester, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F sensor.
Perform the Active Test operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume.)
Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2) 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 B1 S1 or AFS B2 S1 (Air fuel ratio) |
+25% | Rich | Less than 3.0 V |
AFS B1 S1 or AFS B2 S1 (Air fuel ratio) |
-12.5% | Lean | More than 3.35 V |
O2S B1 S2 or O2S B2 S2 (Heated oxygen) |
+25% | Rich | More than 0.55 V |
O2S B1 S2 or O2S B2 S2 (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 |
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1 | - | ||
2 |
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3 |
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4 |
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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.
To display the graph, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2.
Tech Tips
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. 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 DTC OUTPUT (IN ADDITION TO P2195, P2196, P2197 OR P2198)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Turn the tester ON.
Enter the following menus: Powertrain / Engine / DTC.
Read the DTCs.
Result | ||||||
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Tech Tips
If any DTCs other than P2195, P2196, P2197 or P2198 are output, troubleshoot those DTCs first.
B |
GO TO DTC CHART Click here |
A |
READ VALUE USING INTELLIGENT TESTER (TEST VALUE OF AIR FUEL RATIO SENSOR)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Clear the DTCs Click here.
Allow the vehicle to drive in accordance with the drive pattern described in the Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine / Data List / A/F Control System / AFS B1S1 and AFS B2S1.
Check the test value of the air fuel ratio sensor output current during fuel-cut.
Result | ||||||
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B |
REPLACE AIR FUEL RATIO SENSOR Click here |
A |
READ VALUE USING INTELLIGENT TESTER (OUTPUT VOLTAGE OF AIR FUEL RATIO SENSOR)
Connect the intelligent tester to the DLC3.
Start the engine.
Turn the tester ON.
Warm up the air fuel ratio sensor at an engine speed of 2500 rpm for 90 seconds.
Enter the following menus: Powertrain / Engine / Data List / A/F Control System / Snapshot / AFS B1 S1 or AFS B2 S1 and Engine Speed.
Check the air fuel ratio sensor voltage three times, when the engine is in each of the following conditions:
While idling (check for at least 30 seconds)
At an engine speed of approximately 2500 rpm (without any sudden changes in engine speed)
Raise the engine speed to 4000 rpm and then quickly release the accelerator pedal so that the throttle valve is fully closed.
Standard | |||||||||
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Tech Tips
For more information, see the diagrams below.
Tech Tips
If the output voltage of the air fuel ratio sensor remains at approximately 3.3 V (see Malfunction Condition diagram) under any conditions, including those above, the air fuel ratio sensor may have an open circuit. (This will also happen if the air fuel ratio sensor heater has an open circuit.)
If the output voltage of the air fuel ratio 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 air fuel ratio sensor may have a short circuit.
The ECM stops fuel injection (fuel cut) during engine deceleration. This causes a lean condition and results in a momentary increase in the air fuel ratio sensor output voltage.
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 16 km/h (10 mph) to allow the ECM to learn the closed throttle valve position.
When the vehicle is driven:
The output voltage of the air fuel ratio 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 air fuel ratio sensor is functioning normally.
The air fuel ratio 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 air fuel ratio sensor or ECM will show a constant voltage result.
NG |
INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE) Click here |
OK |
PERFORM CONFIRMATION DRIVING PATTERN
NEXT |
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and the tester ON.
Enter the following menus: Powertrain / Engine / DTC.
Read the DTCs.
Result | ||||||
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B |
CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST Click here |
A |
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
NEXT |
PERFORM CONFIRMATION DRIVING PATTERN
NEXT |
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and the tester ON.
Enter the following menus: Powertrain / Engine / DTC / Pending.
Read the DTC.
Result | ||||||
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B |
REPLACE ECM AND PERFORM CONFIRMATION DRIVING PATTERN |
A |
CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST
Has the vehicle run out of fuel in the past?
NO |
CHECK FOR INTERMITTENT PROBLEMS Click here |
YES |
DTC CAUSED BY RUNNING OUT OF FUEL
INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)
Disconnect the air fuel ratio sensor connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance (Bank 1 Sensor 1) | |||||||||
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Standard Resistance (Bank 2 Sensor 1) | |||||||||
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Reconnect the air fuel ratio sensor connector.
NG |
REPLACE AIR FUEL RATIO SENSOR Click here |
OK |
CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)
Disconnect the air fuel ratio sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open) | |||||||||||||||||||||
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Standard Resistance (Check for Short) | |||||||||||||||||||||
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Reconnect the air fuel ratio sensor connector.
Reconnect the ECM connector.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
CHECK INTAKE SYSTEM
Check the intake system for vacuum leaks Click here.
OK |
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No leaks from intake system. |
NG |
REPAIR OR REPLACE INTAKE SYSTEM Click here |
OK |
CHECK FUEL PRESSURE
Check the fuel pressure Click here.
NG |
REPAIR OR REPLACE FUEL SYSTEM (LOW PRESSURE SIDE) |
OK |
INSPECT FUEL INJECTOR FOR PORT INJECTION
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 |
READ VALUE USING INTELLIGENT TESTER (FUEL PRESS)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Start the engine.
Enter the following menus: Powertrain / Engine / Data List / All Data / Fuel Press.
While revving the engine, check that the fuel pressure fluctuates.
Standard |
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Idling |
3.5 to 4.5 MPa (30.6 to 51.0 kgf/cm2, 435 to 725 psi) |
2000 rpm (No load) |
7 to 9 MPa (61.2 to 102.0 kgf/cm2, 870 to 1451 psi) |
Tech Tips
The A/C switch and all accessory switches should be OFF, and the transmission gear selector lever should be in the N or P position, and the engine should be fully warmed up.
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.
NG |
REPLACE FUEL INJECTOR FOR DIRECT INJECTION Click here |
OK |
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
NEXT |
PERFORM CONFIRMATION DRIVING PATTERN
NEXT |
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and the tester ON.
Enter the following menus: Powertrain / Engine /DTC.
Read the DTC.
Result | ||||||
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B |
REPLACE ECM AND PERFORM CONFIRMATION DRIVING PATTERN |
A |
CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST
Has the vehicle run out of fuel in the past?
NO |
CHECK FOR INTERMITTENT PROBLEMS Click here |
YES |
DTC CAUSED BY RUNNING OUT OF FUEL
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
NEXT |
PERFORM CONFIRMATION DRIVING PATTERN
NEXT |
CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Enter the following menus: Powertrain / Engine / DTC.
Read the DTC.
Result | ||||||
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B |
REPLACE ECM Click here |
A |
END