Lexus ES: A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold (P227019,P227118)

Lexus ES (XZ10) Service Manual / Engine & Hybrid System / A25a-fxs (engine Control) / Sfi System / A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold (P227019,P227118)

DESCRIPTION

Refer to DTC P003612.

Click here

HINT:

Although the DTC title say O2 sensor, these DTCs relate to the air fuel ratio sensor (sensor 2).

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P227019	A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold	While the fuel-cut operation is performed (during vehicle deceleration), the air fuel ratio sensor (sensor 2) current is 33.13 mA or more for 0.5 seconds or more (2 trip detection logic).	Open or short in air fuel ratio sensor (sensor 2) circuit Air fuel ratio sensor (sensor 2) Intake system Gas leak from exhaust system Fuel pressure (for high pressure side) Fuel pressure (for low pressure side) Port fuel injector assembly Direct fuel injector assembly Fuel system EGR valve assembly ECM	Comes on	DTC stored	SAE Code: P2270
P227118	A/F (O2) Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2 Circuit Current Below Threshold	While the fuel-cut operation is performed (during vehicle deceleration), the air fuel ratio sensor (sensor 2) current is less than 7.5 mA for 0.5 seconds or more (2 trip detection logic).	Open or short in air fuel ratio sensor (sensor 2) circuit Air fuel ratio sensor (sensor 2) Intake system Gas leak from exhaust system Fuel pressure (for high pressure side) Fuel pressure (for low pressure side) Port fuel injector assembly Direct fuel injector assembly Fuel system EGR valve assembly ECM	Comes on	DTC stored	SAE Code: P2271

HINT:

When any of these DTCs are stored, check the air fuel ratio sensor (sensor 2) current output by entering the following menus on the Techstream: Powertrain / Engine / Data List / A/F (O2) Sensor Current B1S2.
Short-term fuel trim values can also be read using the Techstream.
If an air fuel ratio sensor (sensor 2) malfunction is detected, the ECM will store a DTC.

MONITOR DESCRIPTION

A rich air fuel mixture causes a low air fuel ratio sensor (sensor 2) current, and a lean air fuel mixture causes a high air fuel ratio sensor (sensor 2) 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 (sensor 2) current during fuel-cut and detects any abnormal current values.

If the air fuel ratio sensor (sensor 2) output is 33.13 mA or more for 0.5 seconds or more of cumulative time, the ECM interprets this as a malfunction of the air fuel ratio sensor (sensor 2) and stores DTC P227019 (stuck on high side). If the air fuel ratio sensor (sensor 2) output is less than 7.5 mA for 0.5 seconds or more of cumulative time, the ECM stores DTC P227118 (stuck on low side).

MONITOR STRATEGY

Related DTCs	P2270: Air fuel ratio sensor (sensor 2) signal stuck lean P2271: Air fuel ratio sensor (sensor 2) signal stuck rich
Required Sensors/Components (Main)	Air fuel ratio sensor (sensor 2)
Required Sensors/Components (Related)	Crankshaft position sensor Engine coolant temperature sensor Throttle position sensor
Frequency of Operation	Once per driving cycle
Duration	10 seconds
MIL Operation	2 driving cycles
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored	None
Auxiliary battery voltage	11 V or higher
Engine coolant temperature	75°C (167°F) or higher
Atmospheric pressure	76 kPa(abs) [11 psi(abs)] or higher
Time after engine start	2 seconds or more
Air fuel ratio sensor (sensor 2) malfunction (P22AB, P22AC, P22AD, P22B3, P22B4)	Not detected

TYPICAL MALFUNCTION THRESHOLDS

P2270: Air Fuel Ratio Sensor (Sensor 2) Limit Current (High Side Malfunction)

Duration of following condition	0.5 seconds or more
Air fuel ratio sensor (sensor 2) current	33.13 mA or more

P2271: Air Fuel Ratio Sensor (Sensor 2) Limit Current (Low Side Malfunction)

Duration of following condition	0.5 seconds or more
Air fuel ratio sensor (sensor 2) current	Less than 7.5 mA

MONITOR RESULT

Refer to detailed information in Checking Monitor Status.

Click here

P2270, P2271: O2 Sensor / OUTPUT RATE B1S2

Monitor ID	Test ID	Scaling	Unit	Description
$02	$91	Multiply by 0.004	mA	Output rate bank 1 sensor 2

CONFIRMATION DRIVING PATTERN

HINT:

After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
Click here
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Click here

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG).
Turn the Techstream on.
Enter the following menus: Powertrain / Engine / Monitor / Current Monitor.
Check that Catalyst Efficiency / Current is Incomplete.
Put the engine in Inspection Mode (Maintenance Mode).
Click here
Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher with the shift lever in P [A].
HINT:

In order to keep the idle stable, turn off the A/C and all other electric loads and do not perform any shift operations.
With the engine running, drive the vehicle at approximately 75 km/h (46 mph) for 10 minutes or more [B].
CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.
HINT:
- Drive the vehicle while keeping the engine load as constant as possible.
- If the engine stops, further depress the accelerator pedal to restart the engine.
With the shift lever in S and the engine running, drive the vehicle at 75 km/h (46 mph), and then decelerate the vehicle by releasing the accelerator pedal for 10 seconds or more to perform the fuel-cut [C].
CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

If the engine stops, further depress the accelerator pedal to restart the engine.
Repeat step [C] 2 times or more in one driving cycle.
Enter the following menus: Powertrain / Engine / Trouble Codes / Pending [D].
Read the pending DTCs.
HINT:
- 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 / Utility / All Readiness.
Input the DTC: P227019 or P227118.

Check the DTC judgment result.

Techstream Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

HINT:

If the judgment result is NORMAL, the system is normal.
If the judgment result is ABNORMAL, the system is malfunctioning.
If the judgment result is INCOMPLETE, drive the vehicle with the shift lever in S, and then perform step [C] again.
[A] to [D] : Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

WIRING DIAGRAM

Refer to DTC P003612.

Click here

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Vehicle Control History may be stored in the hybrid vehicle control ECU assembly if the engine is malfunctioning. Certain vehicle condition information is recorded when Vehicle Control History is stored. Reading the vehicle conditions recorded in both the Freeze Frame Data and Vehicle Control History can be useful for troubleshooting.
Click here

(Select Powertrain in Health Check and then check the time stamp data.)

Click here
If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, make sure to clear it. However, as all Vehicle Control History items are cleared simultaneously, if any Vehicle Control History items other than "Engine Malfunction" are stored, make sure to perform any troubleshooting for them before clearing Vehicle Control History.
Click here

HINT:

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 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.

PROCEDURE

1.	CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO P227019 OR P227118)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs.

Powertrain > Engine > Trouble Codes

Result	Proceed to
DTC P227019 or P227118 is output	A
DTC P227019 or P227118 and P00D562 are output
DTC P227019 or P227118 and P013A7C are output
DTC P227019 or P227118 and other DTCs are output	B

HINT:

If any DTCs other than P227019 or P227118 are output, troubleshoot those DTCs first.

GO TO DTC CHART

2.	CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST

(a) Has the vehicle run out of fuel in the past?

GO TO STEP 5

YES

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(e) Turn the power switch off and wait for at least 30 seconds.

4.	CHECK WHETHER DTC OUTPUT RECURS (DTC P227019 OR P227118)

(a) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

(b) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Powertrain > Engine > Utility

Tester Display
All Readiness

(d) Check the DTC judgment result.

Result	Proceed to
NORMAL (DTCs are not output)	A
ABNORMAL (DTC P227019 or P227118 is output)	B

Result

Proceed to

NORMAL

(DTCs are not output)

ABNORMAL

(DTC P227019 or P227118 is output)

DTC CAUSED BY RUNNING OUT OF FUEL

GO TO STEP 5

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(e) Turn the power switch off and wait for at least 30 seconds.

6.	READ VALUE USING TECHSTREAM (TEST VALUE OF AIR FUEL RATIO SENSOR (SENSOR 2))

(a) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

(b) Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / Current.

Powertrain > Engine > Monitor

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

(d) Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / Details / OUTPUT RATE B1S2.

Powertrain > Engine > Monitor

(e) Check the test value of the air fuel ratio sensor (sensor 2) output current during fuel-cut.

Test Value	Proceed to
Within normal range (7.5 mA or more, and less than 33.13 mA)	A
Outside normal range (Less than 7.5 mA, or 33.13 mA or more)	B

GO TO STEP 19

7.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME FOR A/F SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

(f) Idle the engine for 5 minutes or more with the shift lever in P.

(g) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / Data List / Coolant Temperature, A/F (O2) Sensor Current B1S1 and A/F (O2) Sensor Current B1S2.

Powertrain > Engine > Active Test

Active Test Display
Control the Injection Volume for A/F Sensor

Data List Display
Coolant Temperature
A/F (O2) Sensor Current B1S1
A/F (O2) Sensor Current B1S2

(h) Perform the Control the Injection Volume for A/F Sensor operation with the engine idling.

(i) Monitor the output values of the air fuel ratio sensor (sensor 1) and air fuel ratio sensor (sensor 2) (A/F (O2) Sensor Current B1S1 and A/F (O2) Sensor Current B1S2) displayed on the Techstream.

HINT:

The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 12.5%.
The air fuel ratio sensor (sensor 1) has an output delay of a few seconds and the air fuel ratio sensor (sensor 2) has a maximum output delay of approximately 20 seconds.
If the sensor output value does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

Standard

Techstream Display (Sensor)	Injection Volume	Status	Current
A/F (O2) Sensor Current B1S1 (Air fuel ratio (sensor 1))	12.5%	Rich	Below -0.075 mA
A/F (O2) Sensor Current B1S1 (Air fuel ratio (sensor 1))	-12.5%	Lean	More than 0.037 mA
A/F (O2) Sensor Current B1S2 (Air fuel ratio (sensor 2))	12.5%	Rich	Below -0.86 mA
A/F (O2) Sensor Current B1S2 (Air fuel ratio (sensor 2))	-12.5%	Lean	More than 0.33 mA

Status of A/F (O2) Sensor Current B1S1	Status of A/F (O2) Sensor Current B1S2	Air Fuel Ratio Condition and Air Fuel Ratio Sensor (Sensor 2) Condition	Proceed to
Lean	Lean	Actual air fuel ratio lean	A
Rich	Rich	Actual air fuel ratio rich	A
Lean/Rich	Lean	Air fuel ratio sensor (sensor 2) malfunction	B
Lean/Rich	Rich	Air fuel ratio sensor (sensor 2) malfunction
Lean/Rich	Lean/Rich	Normal

Lean: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor (sensor 1) output current (A/F (O2) Sensor Current B1S1) is consistently more than 0.037 mA, and the air fuel ratio sensor (sensor 2) output current (A/F (O2) Sensor Current B1S2) is consistently more than 0.33 mA.
Rich: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor (sensor 1) output current (A/F (O2) Sensor Current B1S1) is consistently below -0.075 mA, and the air fuel ratio sensor (sensor 2) output current (A/F (O2) Sensor Current B1S2) is consistently below -0.86 mA.
Lean/Rich: During the Control the Injection Volume for A/F Sensor Active Test, the output current of the air fuel ratio sensor (sensor 1) or air fuel ratio sensor (sensor 2) alternate correctly.

HINT:

Refer to "Data List / Active Test" [A/F (O2) Sensor Current B1S1, A/F (O2) Sensor Current B1S2].

Click here

GO TO STEP 19

8.	CHECK INTAKE SYSTEM

(a) Check the intake system for vacuum leaks.

Click here

OK:

No leaks in the intake system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the intake system.

Click here

REPAIR OR REPLACE INTAKE SYSTEM

9.	CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks in exhaust system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the exhaust system.

Click here

REPAIR OR REPLACE EXHAUST SYSTEM

10.	PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(e) Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher.

HINT:

The A/C switch and all accessories should be off.

(f) Enter the following menus: Powertrain / Engine / Active Test / Control the EGR Step Position / Data List / Intake Manifold Absolute Pressure, Coolant Temperature and Engine Independent.

Powertrain > Engine > Active Test

Active Test Display
Control the EGR Step Position

Data List Display
Intake Manifold Absolute Pressure
Coolant Temperature
Engine Independent

(g) Confirm that the value of Data List item Engine Independent is "Operate" then check the value of Intake Manifold Absolute Pressure while performing the Active Test.

NOTICE:

Make sure that the value of Data List item Engine Independent is "Operate" while performing the Active Test.
Do not leave the EGR valve open for 10 seconds or more during the Active Test.
Be sure to return the EGR valve to step 0 when the Active Test is completed.
Do not open the EGR valve 30 steps or more during the Active Test.

OK:

The value of Intake Manifold Absolute Pressure changes in response to the EGR step position when the value of Engine Independent is "Operate".

Standard:

EGR Step Position (Active Test)

0 Steps

0 to 30 Steps

Intake Manifold Absolute Pressure

(Data List)

(EGR valve is fully closed)

Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

HINT:

If the value of Data List item Engine Independent is "Not Opr" when the engine is idling, charge control is being performed. Perform the Active Test after charge control is complete ("Operate" is displayed).
While performing the Active Test, if the increase in the value of Intake Manifold Absolute Pressure is small, the EGR valve assembly may be malfunctioning.
Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of Intake Manifold Absolute Pressure may occur while performing the Active Test. However, the amount that the value of Intake Manifold Absolute Pressure increases will be smaller than normal.

GO TO STEP 12

11.	INSPECT EGR VALVE ASSEMBLY

(a) Remove the EGR valve assembly.

Click here

(b) Check if the EGR valve is stuck open.

OK:

EGR valve is tightly closed.

HINT:

Perform "Inspection After Repair" after replacing the EGR valve assembly.

Click here

REPLACE EGR VALVE ASSEMBLY

12.	CHECK FUEL PRESSURE (FOR LOW PRESSURE SIDE)

(a) Check the fuel pressure (for low pressure side).

Click here

GO TO STEP 22

13.	INSPECT PORT FUEL INJECTOR ASSEMBLY

(a) Inspect the port fuel injector assembly (whether fuel volume is high or low, and whether injection pattern is poor).

Click here

HINT:

Perform "Inspection After Repair" after replacing the port fuel injector assembly.

Click here

REPLACE PORT FUEL INJECTOR ASSEMBLY

14.	READ VALUE USING TECHSTREAM (FUEL PRESSURE (HIGH))

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Put the engine in Inspection Mode (Maintenance Mode).

Powertrain > Hybrid Control > Utility

Tester Display
Inspection Mode

(e) Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher with all the accessories switched off.

(f) Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Coolant Temperature, Fuel Pressure (High) and Injection Mode.

Powertrain > Engine > Data List

Tester Display
Engine Speed
Coolant Temperature
Fuel Pressure (High)
Injection Mode

(g) According to the display on the Techstream, read the Data List.

HINT:

During charge control, the engine speed is set at idle. Therefore, the engine speed will not increase when the accelerator pedal is depressed. In this case, read the Data List after charge control has completed.

Standard:

Techstream Display	Condition	Specified Condition
Fuel Pressure (High)	Shift position: P A/C: Off Engine warmed up Engine Speed: 2500 rpm Injection Mode: Direct	3000 to 25000 kPa

REPAIR OR REPLACE FUEL SYSTEM (FOR HIGH PRESSURE SIDE)

15.	INSPECT DIRECT FUEL INJECTOR ASSEMBLY

(a) Inspect the direct fuel injector assembly.

Click here

HINT:

Perform "Inspection After Repair" after replacing the direct fuel injector assembly.

Click here

REPLACE DIRECT FUEL INJECTOR ASSEMBLY

16.	REPLACE AIR FUEL RATIO SENSOR (SENSOR 2)

(a) Replace the air fuel ratio sensor (sensor 2).

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 2).

Click here

17.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(e) Turn the power switch off and wait for at least 30 seconds.

18.	CHECK WHETHER DTC OUTPUT RECURS (DTC P227019 OR P227118)

(a) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

(b) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Powertrain > Engine > Utility

Tester Display
All Readiness

(d) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

ABNORMAL

(DTC P227019 or P227118 is output)

END

REPLACE ECM

19.	REPLACE AIR FUEL RATIO SENSOR (SENSOR 2)

(a) Replace the air fuel ratio sensor (sensor 2).

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 2).

Click here

20.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(e) Turn the power switch off and wait for at least 30 seconds.

21.	CHECK WHETHER DTC OUTPUT RECURS (DTC P227019 OR P227118)

(a) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

(b) Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Powertrain > Engine > Utility

Tester Display
All Readiness

(d) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

ABNORMAL

(DTC P227019 or P227118 is output)

END

REPLACE ECM

22.	CHECK FUEL LINE

(a) Check the fuel lines for leaks or blockage.

HINT:

Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

Click here

REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)

REPAIR OR REPLACE FUEL SYSTEM

SEE MORE:

Dtc Check / Clear

DTC CHECK / CLEAR CHECK DTC (a) Connect the Techstream to the DLC3. (b) Turn the engine switch on (IG). (c) Turn the Techstream on. (d) Enter the following menus: Chassis > Front Recognition Camera > Trouble Codes (e) Check for DTCs (Test Failed / Pending / Confirmed). Techstream Display

Brake System Control Module "A" System Voltage System Voltage Low (C137BA2)

DESCRIPTION If a malfunction is detected in the power supply circuit, the skid control ECU (brake actuator assembly) stores this DTC and the fail-safe function prohibits ABS operation. This DTC is stored when the +BS terminal voltage meets one of the DTC detection conditions due to a malfunction in

Lexus ES: A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold (P227019,P227118)

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