P2198
2GR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2195-P2198: Oxygen (A/F) Sensor Signal Stuck Lean (Bank 1 Sensor 1)
DESCRIPTION
HINT
Although the DTC titles include oxygen sensor, these DTCs relate to the Air-Fuel Ratio (A/F) sensor.
The A/F sensor generates 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 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.
HINT
- DTCs P2195 and P2196 indicate malfunctions related to the bank 1 A/F sensor circuit.
- DTCs P2197 and P2198 indicate malfunctions related to the bank 2 A/F sensor circuit.
- When any of these DTCs are set, check the A/F sensor output voltage by entering the following menus on Techstream: Powertrain / Engine / Data List / AFS Voltage B1S1 or AFS Voltage B2S1.
- Short-term fuel trim values can also be read using Techstream.
- The ECM 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 Techstream.
- If a A/F 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 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 stores DTC P2195 or P2197 (stuck on high side). If the air fuel ratio sensor output is less than 0.78 mA for more than 3 seconds of cumulative time, the ECM stores DTC P2196 or P2198 (stuck on low side).
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All
Sensor Voltage Detection Monitor
Sensor Current Detection Monitor
TYPICAL MALFUNCTION THRESHOLDS
P2195 and P2197: Sensor Voltage Detection Monitor (Lean Side Malfunction)
P2196 and P2198: Sensor Voltage Detection Monitor (Rich Side Malfunction)
P2195 and P2197: Sensor Current Detection Monitor (High Side Malfunction)
P2196 and P2198: Sensor Current Detection Monitor (Low Side Malfunction)
MONITOR RESULT
Refer to Checking Monitor Status Mode 6 Data.
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Turn the Techstream on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.
5. Turn the engine switch off and wait for at least 30 seconds.
6. Turn the engine switch on (IG) and turn the Techstream on.
7. Start the engine, and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [A].
8. On the Techstream, enter the following menus to check the fuel-cut status: Powertrain / Engine / Data List / All Data / Idle Fuel Cut.
9. 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.
10. With the shift lever in S [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.
11. 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:
- Accelerator pedal is fully released.
- Engine speed is 2500 rpm or more (fuel injection returns at 1400 rpm).
12. Allow the vehicle to decelerate until the vehicle speed decreases to less than 10 km/h (6 mph).
13. Repeat steps [C] through [E] above at least 3 times in one driving cycle.
14. Enter the following menus: Powertrain / Engine / Trouble Codes / Pending.
15. Read the pending DTC [F].
HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
16. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
17. Input the DTC: P2195, P2196, P2197 or P2198.
18. Check the DTC judgment result.
HINT
- 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.
19. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
- Read freeze frame data using 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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction Freeze Frame Data.
- 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.
- 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.
- Bank 1 refers to the bank that includes the No. 1 cylinder*.
*: The No. 1 cylinder is the cylinder which is farthest from the 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.
PROCEDURE
1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2195, P2196, P2197 OR P2198)
(a) Connect Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read DTCs.
Result:
HINT
If any DTCs relating to the A/F sensor (DTCs for the A/F sensor heater or A/F sensor admittance) are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART SFI System
A -- Continue to next step.
2. CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST
(a) Has the vehicle run out of fuel on the past?
NO -- READ VALUE USING TECHSTREAM (TEST VALUE OF A/F SENSOR)
YES -- Continue to next step.
3. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG) and turn the Techstream on.
(g) Start the engine and warm it up.
(h) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
(j) Input the DTC: P2195, P2196, P2197 or P2198.
(k) Check the DTC judgment result.
Result:
B -- READ VALUE USING TECHSTREAM (TEST VALUE OF A/F SENSOR)
A -- DTC CAUSED BY RUNNING OUT OF FUEL
4. READ VALUE USING TECHSTREAM (TEST VALUE OF A/F SENSOR)
(a) Connect Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(f) Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / Current.
(g) Check that the status of O2 Sensor is Complete. If the status is still Incomplete, drive the vehicle according to the driving pattern again.
(h) Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / Details / RANGE B1S1 or RANGE B2S1.
(i) Check the test value of the A/F sensor output current during fuel-cut.
Result:
B -- REPLACE AIR FUEL RATIO SENSOR
A -- Continue to next step.
5. READ VALUE USING TECHSTREAM (OUTPUT VOLTAGE OF A/F SENSOR)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Turn the Techstream on.
(d) Warm up the air fuel ratio sensor at an engine speed of 2500 rpm for 90 seconds.
(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume / Gas AF Control / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.
(f) Perform the Control the Injection Volume operation with the engine idling.
(g) 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 Techstream.
HINT
- Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations.
- 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.
Result
Lean: During the Control the Injection Volume Active Test, the air fuel ratio sensor output voltages (AFS Voltage B1S1 and AFS Voltage B2S1) are consistently higher than 3.4 V, and the heated oxygen sensor output voltages (O2S B1S2 and O2S B2S2) are consistently below 0.4 V.
Rich: During the Control the Injection Volume Active Test, the AFS Voltage B1S1 and AFS Voltage B2S1 are consistently below 3.1 V, and the O2S B1S2 and O2S B2S2 are 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, AFS Voltage B2S1, O2S B1S2 and O2S B2S2] Data List / Active List.
B -- REPLACE AIR FUEL RATIO SENSOR
A -- Continue to next step.
6. CHECK AIR INDUCTION SYSTEM
(a) Check the air induction system for vacuum leaks.
OK:
No leaks in air induction system.
NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK -- Continue to next step.
7. CHECK FOR EXHAUST GAS LEAK
(a) Check for exhaust leaks.
OK:
No gas leaks.
NG -- REPAIR OR REPLACE EXHAUST GAS LEAK POINT
OK -- Continue to next step.
8. CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
(a) Check the fuel pressure (low pressure side) Testing and Inspection.
NG -- REPAIR OR REPLACE FUEL SYSTEM (LOW PRESSURE SIDE)
OK -- Continue to next step.
9. CHECK FUEL INJECTOR (FOR PORT INJECTION)
(a) Check the injector injection (for port injection) (whether fuel volume is high or low, and whether injection pattern is poor) Fuel Injector (for Port Injection).
NG -- REPLACE FUEL INJECTOR (FOR PORT INJECTION) Removal
OK -- Continue to next step.
10. CHECK FUEL PRESSURE (HIGH PRESSURE SIDE)
(a) Check the fuel pressure (high pressure side) Testing and Inspection.
NG -- REPAIR OR REPLACE FUEL SYSTEM (HIGH PRESSURE SIDE)
OK -- Continue to next step.
11. CHECK FUEL INJECTOR (FOR DIRECT INJECTION)
(a) Check the fuel injector (for direct injection) Fuel Injector (for Direct Injection).
NG -- REPLACE FUEL INJECTOR (FOR DIRECT INJECTION) Removal
OK -- Continue to next step.
12. REPLACE AIR FUEL RATIO SENSOR
(a) Replace the A/F sensor Removal.
NEXT -- Continue to next step.
13. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
(a) Connect Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG) and turn the Techstream on.
(g) Start the engine and warm it up.
(h) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
(j) Input the DTC: P2195, P2196, P2197 or P2198.
(k) Check the DTC judgment result.
Result:
B -- END
A -- Continue to next step.
14. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- Continue to next step.
15. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG) and turn the Techstream on.
(g) Start the engine and warm it up.
(h) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
(j) Input the DTC: P2195, P2196, P2197 or P2198.
(k) Check the DTC judgment result.
Result
NEXT -- END
16. REPLACE AIR FUEL RATIO SENSOR
(a) Replace the air fuel ratio sensor Removal.
NEXT -- Continue to next step.
17. CHECK WHETHER DTC OUTPUT RECURS (DTC P2195, P2196, P2197 OR P2198)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG) and turn the Techstream on.
(g) Start the engine and warm it up.
(h) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
(j) Input the DTC: P2195, P2196, P2197 or P2198.
(k) Check the DTC judgment result.
Result:
B -- REPLACE ECM Removal
A -- END