DTC P2A00-26: O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 Signal Rate of Change Below Threshold [03/2022 - ]: Procedure

1. Read the DTCs.

   Powertrain > Engine > Trouble Codes 

   Result

   Result	Proceed to
   DTC P2A00-26 is output	A
   DTC P2A00-26 and other DTCs are output	B

   HINT: 

   If any DTCs other than P2A00-26 are output, troubleshoot those DTCs first.

Result: 

B 

GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2022 - 03/2023]  , or Refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2023 - 03/2024]  , or Refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2024 - ] 

Result: 

A 

See step  2

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

   Powertrain > Engine > Data List 

   Tester Display
   Coolant Temperature

2. Warm up the air fuel ratio sensors at an engine speed of 2500 rpm for 90 seconds.
3. Perform the Control the Injection Volume for A/F Sensor operation with the engine idling.

   Powertrain > Engine > Active Test 

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

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

4. 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 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 (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
   
   

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

   Result

   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 1) 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 (sensor 1) malfunction	C
   Rich	Lean/Rich	Air fuel ratio sensor (sensor 1) malfunction

   1. 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.
   2. 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.
   3. 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 Voltage B1S1, A/F (O2) Sensor Voltage B2S1, A/F (O2) Sensor Current B1S2 and A/F (O2) Sensor Current B2S2].

   Refer to DATA LIST / ACTIVE TEST [03/2022 - 03/2023] , or refer to DATA LIST / ACTIVE TEST [03/2023 - ]

Result: 

B 

See step  7

Result: 

C 

See step  16

Result: 

A 

See step  3

1. Clear the DTCs.

   Powertrain > Engine > Clear DTCs 

2. Turn the ignition switch off and wait for at least 30 seconds.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  4

1. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
2. Input the DTC: P2A00-26.

   Powertrain > Engine > Utility 

   Tester Display
   All Readiness

3. Check the DTC judgment result.

   Result

   Result	Proceed to
   NORMAL (DTCs are not output)	A
   ABNORMAL (DTC P2A00-26 is output)	B

Result: 

A 

END 

Result: 

B 

See step  5

1. 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.

   Powertrain > Engine > Data List 

   Tester Display
   Coolant Temperature

2. Check the engine idling condition and Intake Manifold Absolute Pressure values in the Data List while performing the Active Test.

   Powertrain > Engine > Active Test 

   Active Test Display
   Control the EGR Step Position

   Data List Display
   Engine Speed
   Intake Manifold Absolute Pressure

   NOTE:

   • 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 and Engine Speed change in response to EGR step position.

   Standard

   -	Control the EGR Step Position (Active Test)
   	0 Steps	0 to 30 Steps
   Idling condition	Steady idling	Idling changes from steady to rough idling or engine stalls
   Intake Manifold Absolute Pressure (Data List)	Intake Manifold Absolute Pressure value is 20 to 40 kPa (abs) (2.9 to 5.8 psi (abs)) (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: 

   During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  16

Result: 

NG 

See step  6

1. Remove the EGR valve assembly.

   Refer to REMOVAL [11/2021 - ]

2. 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.

   Refer to INITIALIZATION [11/2021 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  16

Result: 

NG 

REPLACE EGR VALVE ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Refer to INSPECTION [11/2021 - ]

HINT: 

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 1).

Refer to INITIALIZATION [11/2021 - ]

Result

Result: 

NG 

REPLACE AIR FUEL RATIO SENSOR (SENSOR 1). Refer to  REMOVAL [11/2021 - ] 

Result: 

OK 

See step  8

1. Check the intake system for vacuum leaks.

   Refer to ON-VEHICLE INSPECTION [11/2021 - ]

   OK

   No leaks in the intake system.

   HINT: 

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

   Refer to INITIALIZATION [11/2021 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE INTAKE SYSTEM 

Result: 

OK 

See step  9

OK

No gas leaks.

HINT: 

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

Refer to INITIALIZATION [11/2021 - ]

Result

Result: 

NG 

REPAIR OR REPLACE EXHAUST SYSTEM 

Result: 

OK 

See step  10

1. 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.

   Powertrain > Engine > Data List 

   Tester Display
   Coolant Temperature

2. Check the engine idling condition and Intake Manifold Absolute Pressure values in the Data List while performing the Active Test.

   Powertrain > Engine > Active Test 

   Active Test Display
   Control the EGR Step Position

   Data List Display
   Engine Speed
   Intake Manifold Absolute Pressure

   NOTE:

   • 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 and Engine Speed change in response to EGR step position.

   Standard

   -	Control the EGR Step Position (Active Test)
   	0 Steps	0 to 30 Steps
   Idling condition	Steady idling	Idling changes from steady to rough idling or engine stalls
   Intake Manifold Absolute Pressure (Data List)	Intake Manifold Absolute Pressure value is 20 to 40 kPa (abs) (2.9 to 5.8 psi (abs)) (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: 

   During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  12

Result: 

NG 

See step  11

1. Remove the EGR valve assembly.

   Refer to REMOVAL [11/2021 - ]

2. 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.

   Refer to INITIALIZATION [11/2021 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE EGR VALVE ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

OK 

See step  12

Refer to PROCEDURE - Step 2

Result

Result: 

NG 

See step  19

Result: 

OK 

See step  13

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

   Refer to INSPECTION [11/2021 - ]

   HINT: 

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

   Refer to INITIALIZATION [11/2021 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE PORT FUEL INJECTOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

OK 

See step  14

1. 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.

   Powertrain > Engine > Data List 

   Tester Display
   Coolant Temperature

2. According to the display on the Techstream, read the Data List.

   Powertrain > Engine > Data List 

   Tester Display
   Engine Speed
   Fuel Pressure (High)
   Injection Mode

   Standard

   Techstream Display	Condition	Specified Condition
   Fuel Pressure (High)	Shift position: P A/C: Off Engine warmed up Engine Speed: 3000 rpm Injection Mode: Direct	2400 to 20000 kPag

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE FUEL SYSTEM (FOR HIGH PRESSURE) 

Result: 

OK 

See step  15

Refer to INSPECTION [11/2021 - ]

HINT: 

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

Refer to INITIALIZATION [11/2021 - ]

Result

Result: 

NG 

REPLACE DIRECT FUEL INJECTOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

OK 

See step  16

Refer to REMOVAL [11/2021 - ]

HINT: 

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 1).

Refer to INITIALIZATION [11/2021 - ]

Result

Result: 

NEXT 

See step  17

1. Clear the DTCs.

   Powertrain > Engine > Clear DTCs 

2. Turn the ignition switch off and wait for at least 30 seconds.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  18

1. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
2. Input the DTC: P2A00-26.

   Powertrain > Engine > Utility 

   Tester Display
   All Readiness

3. Check the DTC judgment result.

   Result

   Result	Proceed to
   NORMAL (DTCs are not output)	A
   ABNORMAL (DTC P2A00-26 is output)	B

Result: 

A 

END 

Result: 

B 

REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

1. Check the fuel lines (for low pressure side) for leaks or blockage.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

GO TO FUEL PUMP CONTROL CIRCUIT. Refer to  Fuel Pump Control Circuit [03/2022 - ] 

Result: 

NG 

REPAIR OR REPLACE FUEL LINE (FOR LOW PRESSURE SIDE)