Last Modified: 05-13-2024 |
6.11:8.1.0 |
Doc ID: RM1000000026JSR |
Model Year Start: 2023 |
Model: Corolla |
Prod Date Range: [09/2022 -
] |
Title: 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: P2A0026; O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 Signal Rate of Change Below Threshold; 2023 - 2025 MY Corolla Corolla HV [09/2022 - ] |
DTC
|
P2A0026
|
O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 Signal Rate of Change Below Threshold
|
DESCRIPTION
Refer to DTC P219519.
Click here
HINT:
Although the DTC titles say oxygen sensor, this DTC relate to the air fuel ratio sensor (sensor 1).
DTC No.
|
Detection Item
|
DTC Detection Condition
|
Trouble Area
|
MIL
|
Memory
|
Note
|
P2A0026
|
O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 Signal Rate of Change Below Threshold
|
The calculated value for the air fuel ratio sensor (sensor 1) response rate deterioration level is less than the threshold (2 trip detection logic).
|
-
Air fuel ratio sensor (sensor 1)
-
Intake system
-
Port fuel injector assembly
-
Direct fuel injector assembly
-
Fuel pressure (for low pressure)
-
Fuel pressure (for high pressure)
-
Fuel system
-
EGR valve assembly
-
ECM
|
Comes on
|
DTC stored
|
-
SAE Code: P2A00
-
DTC for Mexico Models: Applies (Mexico models only)
|
MONITOR DESCRIPTION
After the engine is warmed up, the ECM performs air fuel ratio feedback control to maintain the air fuel ratio at the stoichiometric level. In addition, active air fuel ratio control is performed for approximately 30 seconds after preconditions are met in order to measure the air fuel ratio sensor (sensor 1) response rate. During active air fuel ratio control, the ECM forcibly increases and decreases the injection volume by a certain amount, based on the stoichiometric air fuel ratio learned during normal air fuel ratio control, and measures the air fuel ratio sensor (sensor 1) response rate. The ECM receives a signal from the air fuel ratio sensor (sensor 1) while performing active air fuel ratio control and uses it to calculate the air fuel ratio sensor (sensor 1) response rate deterioration level.
If the value for the air fuel ratio sensor (sensor 1) response rate deterioration level is less than the threshold, the ECM interprets this as a malfunction and stores the DTC.
MONITOR STRATEGY
Required Sensors/Components
|
Air fuel ratio sensor (sensor 1)
|
Frequency of Operation
|
Once per driving cycle
|
TYPICAL ENABLING CONDITIONS
Active air fuel ratio control
|
Performing
|
Active air fuel ratio control performed when following conditions met
|
-
|
Engine coolant temperature
|
75°C (167°F) or higher
|
Idling
|
Off
|
Engine speed
|
Less than 4000 rpm
|
Air fuel ratio sensor status
|
Activated
|
Engine load
|
10% or higher, and less than 100%
|
Catalyst monitor
|
Not yet
|
Mass air flow
|
5 gm/sec or more, and less than 14 gm/sec
|
CONFIRMATION DRIVING PATTERN
HINT:
Performing this confirmation driving pattern will activate the air fuel ratio sensor response monitor.
-
Connect the GTS to the DLC3.
-
Turn the power switch on (IG).
-
Turn the GTS 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 GTS on.
-
Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [A].
-
With the engine running, drive the vehicle at approximately 60 to 100 km/h (37 to 62 mph) for 10 minutes or more in a city area [B].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
-
Enter the following menus: Powertrain / Engine / Trouble Codes [C].
-
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: P2A0026.
-
Check the DTC judgment result.
GTS 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 shows NORMAL, the system is normal.
-
If the judgment result shows ABNORMAL, the system has a malfunction.
-
If the judgment result shows INCOMPLETE and no pending DTC is output, perform the following procedure.
-
With the engine running, drive the vehicle at a speed between 75 and 100 km/h (47 and 62 mph) for 10 minutes [D].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
-
Enter the following menus: Powertrain / Engine / Trouble Codes [E].
-
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: P2A0026.
-
Check the DTC judgment result.
GTS 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 shows NORMAL, the system is normal.
-
If the judgment result shows ABNORMAL, the system has a malfunction.
-
If the judgment result shows INCOMPLETE, drive the vehicle again under an increased load and then recheck the judgment result.
WIRING DIAGRAM
Refer to DTC P219519.
Click here
CAUTION / NOTICE / HINT
HINT:
-
DTC P2A0026 may be also stored when the air fuel ratio is stuck at rich or lean.
-
A low air fuel ratio sensor (sensor 1) 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 (sensor 1) voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.
-
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.
PROCEDURE
1.
|
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2A0026)
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Powertrain > Engine > Trouble Codes
Result
|
Proceed to
|
DTC P2A0026 is output
|
A
|
DTC P2A0026 and other DTCs are output
|
B
|
HINT:
If any DTCs other than P2A0026 are output, troubleshoot those DTCs first.
A
|
|
|
2.
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE INJECTION VOLUME FOR A/F SENSOR)
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(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.
(f) Idle the engine for 5 minutes or more with park (P) selected.
(g) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / Data List / A/F (O2) Sensor Current B1S1 and O2 Sensor Voltage B1S2.
Powertrain > Engine > Active Test
Active Test Display
|
Control the Injection Volume for A/F Sensor
|
Data List Display
|
A/F (O2) Sensor Current B1S1
|
O2 Sensor Voltage B1S2
|
(h) Change the fuel injection volume using the GTS, and monitor the output voltage of the air fuel ratio sensor (A/F (O2) Sensor Current B1S1) and heated oxygen sensor (O2 Sensor Voltage B1S2) displayed on the GTS.
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 is displayed as A/F (O2) Sensor Current B1S1, and the heated oxygen sensor is displayed as O2 Sensor Voltage B1S2 on the GTS.
-
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.
Standard:
GTS Display (Sensor)
|
Injection Volume
|
Status
|
Voltage
|
A/F (O2) Sensor Current B1S1
(Air fuel ratio)
|
12.5%
|
Rich
|
Below -0.075 mA
|
-12.5%
|
Lean
|
Higher than 0.037 mA
|
O2 Sensor Voltage B1S2
(Heated oxygen)
|
12.5%
|
Rich
|
Higher than 0.55 V
|
-12.5%
|
Lean
|
Below 0.4 V
|
Status of A/F (O2) Sensor Current B1S1
|
Status of O2 Sensor Voltage B1S2
|
Air Fuel Ratio Condition and Air Fuel Ratio Sensor Condition
|
Proceed to
|
Lean/Rich
|
Lean/Rich
|
Normal
|
A
|
Lean
|
Lean
|
Actual air fuel ratio lean
|
B
|
Rich
|
Rich
|
Actual air fuel ratio rich
|
Lean
|
Lean/Rich
|
Air fuel ratio sensor malfunction
|
C
|
Rich
|
Lean/Rich
|
Air fuel ratio sensor malfunction
|
A
|
|
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs
(e) Turn the power switch off and wait for at least 30 seconds.
NEXT
|
|
|
4.
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2A0026)
|
(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
|
(c) Input the DTC: P2A0026.
(d) Check the DTC judgment result.
Result
|
Proceed to
|
NORMAL
(DTCs are not output)
|
A
|
ABNORMAL
(DTC P2A0026 is output)
|
B
|
A |
|
END
|
B
|
|
|
5.
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(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 and Engine Independent.
Powertrain > Engine > Active Test
Active Test Display
|
Control the EGR Step Position
|
Data List Display
|
Intake Manifold Absolute Pressure
|
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:
-
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:
-
|
Control the 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 (75 mmHg) 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.
NG
|
|
|
6.
|
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
7.
|
INSPECT AIR FUEL RATIO SENSOR (SENSOR 1) (HEATER RESISTANCE)
|
(a) Inspect the air fuel ratio sensor (sensor 1).
Click here
HINT:
Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 1).
Click here
OK
|
|
|
(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
NG |
|
REPAIR OR REPLACE INTAKE SYSTEM
|
OK
|
|
|
9.
|
CHECK FOR EXHAUST GAS LEAK
|
(a) Check for exhaust gas leaks.
OK:
No gas leaks.
HINT:
Perform "Inspection After Repair" after repairing or replacing the exhaust system.
Click here
NG |
|
REPAIR OR REPLACE EXHAUST SYSTEM
|
OK
|
|
|
10.
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(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 and Engine Independent.
Powertrain > Engine > Active Test
Active Test Display
|
Control the EGR Step Position
|
Data List Display
|
Intake Manifold Absolute Pressure
|
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:
-
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:
-
|
Control the 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 (75 mmHg) 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.
NG
|
|
|
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
OK
|
|
|
(a) Check the fuel pressure.
Click here
OK
|
|
|
13.
|
INSPECT FUEL INJECTOR ASSEMBLY
|
(a) Inspect the fuel injector assembly.
Click here
HINT:
Perform "Inspection After Repair" after replacing the fuel injector assembly.
Click here
(a) Inspect the fuel pump.
Click here
HINT:
Perform "Inspection After Repair" after replacing the fuel pump.
Click here
OK |
|
REPAIR OR REPLACE FUEL LINE
|
15.
|
REPLACE AIR FUEL RATIO SENSOR
|
(a) Replace the air fuel ratio sensor.
Click here
HINT:
Perform "Inspection After Repair" after replacing the air fuel ratio sensor.
Click here
NEXT
|
|
|
(a) Connect the GTS to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the GTS on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs
(e) Turn the power switch off and wait for at least 30 seconds.
NEXT
|
|
|
17.
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2A0026)
|
(a) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(b) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Powertrain > Engine > Utility
Tester Display
|
All Readiness
|
(c) Input the DTC: P2A0026.
(d) Check the DTC judgment result.
Result
|
Proceed to
|
NORMAL
(DTC is not output)
|
A
|
ABNORMAL
(DTC P2A0026 is output)
|
B
|
A |
|
END
|
|