SFI SYSTEM (w/ EGR System), Diagnostic DTC:P2A00, P2A03

DTC Code DTC Name
P2A00 A/F Sensor Circuit Slow Response (Bank 1 Sensor 1)
P2A03 A/F Sensor Circuit Slow Response (Bank 2 Sensor 1)

DESCRIPTION

Refer to DTC P2195 Click here.

Tech Tips


  • DTC P2A00 indicates malfunctions related to the bank 1 air fuel ratio sensor.

  • DTC P2A03 indicates malfunctions related to the bank 2 air fuel ratio sensor.

  • Bank 1 refers to the bank that includes cylinder No. 1.

  • Bank 2 refers to the bank that does not include cylinder No. 1.

  • Sensor 1 refers to the sensor mounted in front of the three-way catalytic converter and located near the engine assembly.

DTC No. DTC Detection Condition Trouble Area

P2A00

P2A03

Calculated value for air fuel ratio sensor response rate deterioration level is less than threshold

(2 trip detection logic)

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • Air fuel ratio sensor (bank1, 2 sensor 1) heater

  • EGR valve assembly

  • ECM

CONFIRMATION DRIVING PATTERN

Tech Tips

Performing this confirmation pattern will activate the air fuel ratio sensor response monitor.

A01NHK4E08

  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the tester on.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Click here.

  5. Put the engine in inspection mode Click here.

  6. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or more) [B].

  7. Drive the vehicle at a constant speed of between 75 and 100 km/h (47 and 62 mph) for 10 minutes [C].

  8. Enter the following menus: Powertrain / Engine and ECT / DTC / Pending [D].

  9. Read the pending DTC.

  10. If a pending DTC is output, the system is malfunctioning.

    Tech Tips

    If a pending DTC is not output, perform the following procedure.

  11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  12. Input the DTC: P2A00 or P2A03.

  13. Check the DTC judgment result.

    Tester 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
    UNKNOWN

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips

    If the judgment result shows ABNORMAL, the system has a malfunction.

WIRING DIAGRAM

Refer to DTC P2195 Click here.

INSPECTION PROCEDURE

Tech Tips

Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F Sensor 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.


  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the tester on.

  4. Put the engine in inspection mode Click here.

  5. Start the engine.

  6. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.

  7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.

  8. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).

  9. 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 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 in the fuel injection volume.

Tester Display

(Sensor)

 Injection Volume Status Voltage

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 +25% Rich Less than 3.1 V

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 -12.5% Lean More than 3.4 V

O2S B1S2 or O2S B2S2

(Heated oxygen)

 +25% Rich More than 0.55 V

O2S B1S2 or O2S B2S2

(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
1 A01NFFXE12 A01NH0JE12 -
2 A01NE6JE06 A01NH0JE12

  • Air fuel ratio sensor

  • Air fuel ratio sensor heater

  • Air fuel ratio sensor circuit
3 A01NFFXE12 A01NE6JE07

  • Heated oxygen sensor

  • Heated oxygen sensor heater

  • Heated oxygen sensor circuit

  • Exhaust gas leaks
4 A01NE6JE06 A01NE6JE06

  • Fuel pressure

  • Exhaust gas leaks

    (Air fuel ratio extremely lean or rich)

Tech Tips


  • DTC P2A00 or P2A03 may also be set when the air fuel ratio remains rich or lean.

  • 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.

  • Read freeze frame data using the intelligent tester. 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 P2A00 AND/OR P2A03)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / DTC.

    5. Read the DTCs.

      Result
      Result Proceed to
      DTC P2A00 and/or P2A03 are output A
      DTC P2A00 and/or P2A03 and other DTCs are output B

      Tech Tips

      If any DTCs other than P2A00 and/or P2A03 are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)


    1. A01NCV7E09
      Text in Illustration
      *1

      Component without harness connected

      (Air Fuel Ratio Sensor)
      *2 Bank 1
      *3 Bank 2

      Disconnect the air fuel ratio sensor connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (HA1A) - 2 (+B) 20°C (68°F) 1.8 to 3.4 Ω
      1 (HA1A) - 4 (A1A-) Always 10 kΩ or higher
      1 (HA2A) - 2 (+B) 20°C (68°F) 1.8 to 3.4 Ω
      1 (HA2A) - 4 (A2A-) Always 10 kΩ or higher

    3. Reconnect the air fuel ratio sensor connector.


    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)


    1. Disconnect the air fuel ratio sensor connector.

      A01NCUUE04

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      D20-1 (HA1A) - D1-24 (HA1A) Always Below 1 Ω
      D20-3 (A1A+) - D1-100 (A1A+) Always Below 1 Ω
      D20-4 (A1A-) - D1-132 (A1A-) Always Below 1 Ω
      D19-1 (HA2A) - D1-22 (HA2A) Always Below 1 Ω
      D19-3 (A2A+) - D1-99 (A2A+) Always Below 1 Ω
      D19-4 (A2A-) - D1-131 (A2A-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      D20-1 (HA1A) or D1-24 (HA1A) - Body ground Always 10 kΩ or higher
      D20-3 (A1A+) or D1-100 (A1A+) - Body ground Always 10 kΩ or higher
      D20-4 (A1A-) or D1-132 (A1A-) - Body ground Always 10 kΩ or higher
      D19-1 (HA2A) or D1-22 (HA2A) - Body ground Always 10 kΩ or higher
      D19-3 (A2A+) or D1-99 (A2A+) - Body ground Always 10 kΩ or higher
      D19-4 (A2A-) or D1-131 (A2A-) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Air Fuel Ratio Sensor)

      		 *2

      Front view of wire harness connector

      (to ECM)
      *3 Bank 1 *4 Bank 2

    4. Reconnect the ECM connector.

    5. Reconnect the air fuel ratio sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (AIR FUEL RATIO SENSOR - ECM)

    OK

  4. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

    9. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

    10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    11. Input the DTC: P2A00 or P2A03.

    12. Check the DTC judgment result.

      Result
      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P2A00 or P2A03 is output) B

    B

    REPLACE AIR FUEL RATIO SENSOR Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

  5. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  6. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

    9. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

    10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    11. Input the DTC: P2A00 or P2A03.

    12. Check the DTC judgment result.

      Result
      Result Proceed to
      ABNORMAL (DTC P2A00 or P2A03 is output) A
      NORMAL (DTC is not output) B

    B

    END

    A

  7. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

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

      Tech Tips

      The A/C switch and all accessory switches should be off.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / All Data / Throttle Idle Position and MAP.

    7. Confirm that the Throttle Idle Position is ON and check the MAP value in the Data List while performing the Active Test.

      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
      MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.
      Standard
      - EGR Step Position (Active Test)
      0 Steps 0 to 30 Steps

      MAP

      (Data List)

      		 (EGR valve is fully closed) MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

      Tech Tips


      • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.

      • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

      Result
      Result Proceed to
      Outside of standard range A
      Within standard range B

    B

    REPLACE ECM Click here

    A

  8. INSPECT EGR VALVE ASSEMBLY


    1. Remove the EGR valve assembly Click here.

    2. Check if the EGR valve is stuck open.

      OK
      EGR valve is tightly closed.

    3. Reinstall the EGR valve assembly Click here.


    NG

    REPLACE EGR VALVE ASSEMBLY Click here

    OK

  9. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  10. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTC Click here.

    5. Turn the power switch off.

    6. Turn the power switch on (IG) and turn the tester on.

    7. Put the engine in inspection mode Click here.

    8. Start the engine and warm it up.

    9. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

    10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    11. Input the DTC: P2A00 or P2A03.

    12. Check the DTC judgment result.


    NEXT

    END