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Home >> Toyota >> 2019 >> 86 Base, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (6 Of 6) >> SFI System >> DTC P2096: Post Catalyst Fuel Trim System Too Lean (Bank 1); DTC P2097: Post Catalyst Fuel Trim System Too Rich (Bank 1) [06/2016 - 12/2017] >> Procedure
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DTC P2096: Post Catalyst Fuel Trim System Too Lean (Bank 1); DTC P2097: Post Catalyst Fuel Trim System Too Rich (Bank 1) [06/2016 - 12/2017]: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2096 AND/OR P2097) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Trouble Codes.
    5. Read the DTCs.

      Result

      Result Proceed to
      P2096 or P2097 A
      P2096 and/or P2097 and other DTCs B

      HINT: 

      If any DTCs other than P2096 or P2097 are output, troubleshoot those DTCs first.

    Result: 

    GO TO DTC CHART 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [06/2016 - 03/2017] , or refer to DIAGNOSTIC TROUBLE CODE CHART [03/2017 - 07/2018] )

    Result: 

    See step  2

  2. PERFORM SYSTEM CHECK (CONTROL THE INJECTION WAY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Start the engine.
    5. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Port.
    6. Read the value Short #1 and Long FT #1.

      OK

      Short FT #1 + Long FT #1 = Between -19% and +19%

    7. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.
    8. Read the value Short FT #1 and Long FT #1.

      OK

      Short FT #1 + Long FT #1 = Between -19% and +19%

      Result

      Item Proceed to
      Port Direct
      OK OK A
      OK NG B
      NG OK C
      NG NG D

    Result: 

    See step  18

    Result: 

    See step  23

    Result: 

    See step  4

    Result: 

    See step  3

  3. CHECK IF VEHICLE HAS RUN OUT OF FUEL IN PAST 
    1. Has the vehicle run out of fuel in the past?

    Result: 

    YES 

    DTC CAUSED BY RUNNING OUT OF FUEL 

    Result: 

    NO 

    CHECK FOR INTERMITTENT PROBLEMS 

    (Refer to CHECK FOR INTERMITTENT PROBLEMS [06/2016 - ] )

  4. CHECK PCV HOSE CONNECTIONS 
    1. Check the PCV hose connections (Refer to PROCEDURE - Step 1 ).

      OK

      PCV valve and hose are connected correctly and are not damaged.

    Result: 

    NG 

    REPAIR OR REPLACE PCV HOSE 

    Result: 

    OK 

    See step  5

  5. CHECK INTAKE SYSTEM 
    1. Check the intake system for vacuum leaks (Refer to ON-VEHICLE INSPECTION [06/2016 - ] ).

      OK

      No leaks in intake system.

    Result: 

    NG 

    REPAIR OR REPLACE INTAKE SYSTEM 

    Result: 

    OK 

    See step  6

  6. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME FOR A/F SENSOR) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn Techstream on.
    4. Warm up the engine and run the engine at an engine speed of 2500 RPM for approximately 90 seconds.
    5. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / AFS Voltage B1S1 and O2S B1S2.
    6. Perform the Control the Injection Volume for A/F Sensor operation with the engine in an idling.
    7. Monitor the output voltages of the A/F and HO2 sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.

      HINT: 

      • Change the fuel injection volume within the range of -12% to 12%.
      • 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.
      Techstream Display (Sensor) Injection Volume Status Voltage
      AFS Voltage B1S1
      (A/F)
      12% Rich Less than 2.0 V
      -12% Lean More than 2.4 V
      O2S B1S2
      (HO2)
      12% Rich More than 0.55 V
      -12% Lean Less than 0.4 V

      Result

      Status
      AFS Voltage B1S1
      Status
      O2S B1S2
      A/F Condition and
      A/F Sensor Condition
      Suspected Trouble Area Proceed to
      Lean/Rich Lean/Rich Normal - A
      Lean Lean Actual air-fuel ratio lean
      • Ventilation valve and hose
      • Ventilation hose connections
      • Injector for port injection
      • Gas leakage from exhaust system
      • Air induction system
      • Fuel pressure
      • Mass Air Flow (MAF) meter
      • Engine Coolant Temperature (ECT) sensor
      A
      Rich Rich Actual air-fuel ratio rich
      • Gas leakage from exhaust system
      • Ignition system
      • Fuel pressure
      • Mass air flow meter
      • ECT sensor
      A
      Lean Lean/Rich A/F sensor malfunction
      • Air fuel ratio sensor
      B
      Rich Lean/Rich A/F sensor malfunction
      • Air fuel ratio sensor
      B

      Lean: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor output voltage (AFS Voltage) is consistently higher than 2.4 V, and the heated oxygen sensor output voltage (O2S) is consistently below 0.4 V.

      Rich: During the Control the Injection Volume for A/F Sensor Active Test, the AFS Voltage is consistently below 2.0 V, and the O2S is consistently higher than 0.55 V.

      Lean/Rich: During the Control the Injection Volume for A/F Sensor Active Test, the output voltage of the heated oxygen sensor alternates correctly.

      HINT: 

      Refer to "Data List / Active Test" [AFS Voltage B1S1 and O2S B1S2] (Refer to DATA LIST / ACTIVE TEST [06/2016 - ] ).

    Result: 

    See step  10

    Result: 

    See step  7

  7. READ VALUE USING TECHSTREAM (COOLANT TEMP) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.
    5. Read the Coolant Temp twice, when the engine is both cold and warmed up.

      Standard

      With cold engine 

      Same as ambient air temperature.

      With warm engine 

      Between 75 and 100°C (167 and 212°F)

    Result: 

    NG 

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    OK 

    See step  8

  8. READ VALUE USING TECHSTREAM (MAF) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Start the engine.
    5. Enter the following menus: Powertrain / Engine / Data List / MAF, Coolant Temp and Engine Speed.
    6. Allow the engine to idle until Coolant Temp reaches 75°C (167°F) or higher.
    7. Read MAF with the engine speed at 3000 RPM.

      Standard

      Between 13.0 gm/sec and 14.0 gm/sec (shift lever: N, A/C: Off).

    Result: 

    NG 

    See step  24

    Result: 

    OK 

    See step  9

  9. CHECK FOR EXHAUST GAS LEAK 
    1. Check for exhaust gas leaks.

      OK

      No gas leaks.

    Result: 

    OK 

    See step  13

    Result: 

    NG 

    REPAIR OR REPLACE EXHAUST SYSTEM 

  10. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE) 
    1. Inspect the air fuel ratio sensor (Refer to INSPECTION [06/2016 - ] ).

    Result: 

    NG 

    REPLACE AIR FUEL RATIO SENSOR 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM) 
    1. Disconnect the air fuel ratio sensor connector.
    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
      A34-19 (A1A+) - C14-3 (A1A+) Always Below 1 Ω
      A34-18 (A1A-) - C14-4 (A1A-) Always Below 1 Ω
      A34-5 (HA1A) - C14-1 (HA1A) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      A34-19 (A1A+) or C14-3 (A1A+) - Body ground Always 10 kΩ or higher
      A34-18 (A1A-) or C14-4 (A1A-) - Body ground Always 10 kΩ or higher
      A34-5 (HA1A) or C14-1 (HA1A) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. REPLACE AIR FUEL RATIO SENSOR 
    1. Replace the air fuel ratio sensor (Refer to REMOVAL [06/2016 - ] ).

    Result: 

    NEXT 

    See step  13

  13. PERFORM CONFIRMATION DRIVING PATTERN 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON and turn the Techstream on.
    3. Clear the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    4. Turn the ignition switch off and wait for at least 30 seconds.
    5. Turn the ignition switch to ON and turn the Techstream on.
    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    Result: 

    NEXT 

    See step  14

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P2096 AND/OR P2097) 
    1. Enter the following menus: Powertrain / Engine / Trouble Codes.
    2. Read the pending DTCs.

      Result

      Result Proceed to
      P2096 and/or P2097 A
      DTC is not output B

    Result: 

    END 

    Result: 

    See step  15

  15. CHECK FUEL PRESSURE (LOW PRESSURE SIDE) 
    1. Check the fuel pressure (low pressure side) (Refer to ON-VEHICLE INSPECTION [06/2016 - ] ).

      Result

      Result Proceed to
      NG A
      OK B

    Result: 

    See step  24

    Result: 

    See step  16

  16. CHECK FUEL PUMP OPERATION (LOW PRESSURE SIDE) 
    1. Check the fuel pump operation (Refer to PROCEDURE - Step 1 ).

    Result: 

    NG 

    REPLACE FUEL PUMP ASSEMBLY 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    OK 

    See step  17

  17. CHECK FUEL LEAK (LOW PRESSURE SIDE) 
    1. Check for fuel leaks (low pressure side).

      OK

      No leaks.

    Result: 

    OK 

    CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL LINE AND FILTER 

    Result: 

    NG 

    REPAIR OR REPLACE FUEL SYSTEM (LOW PRESSURE SIDE) 

  18. CHECK FUEL PRESSURE SENSOR 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Start the engine.
    5. Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
    6. While revving the engine, check that the fuel pressure fluctuates.

      Standard

      Idling 

      3000 to 5000 kPa (30.6 to 50.9 kgf/cm2 , 436 to 725 psi).

      HINT: 

      The A/C switch and all accessory switches should be off, and the shift lever should be in the N, P or neutral position, and the engine should be fully warmed up.

    Result: 

    NG 

    See step  21

    Result: 

    OK 

    See step  19

  19. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.

      HINT: 

      • The A/C switch and all accessory switches should be off, and the shift lever should be in the N, P or neutral position, and the engine should be fully warmed up.
      • Enter the following menus: Powertrain / Engine / Data List / Injection Switching Status and confirm Injection Switching Status is OK.
    5. Read the value Short FT #1, Long FT #1 and Fuel Pump Duty.

      Result

      Item Proceed to
      Fuel Pump Duty Short FT #1 + Long FT #1
      10% to 40% - A
      40% or more -20% or less B
      10% or less +20% or more B
      40% or more +20% or more C
      10% or less -20% or less D

    Result: 

    REPLACE FUEL PRESSURE SENSOR 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    See step  22

    Result: 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    See step  20

  20. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.

      HINT: 

      • The A/C switch and all accessory switches should be off, and the shift lever should be in the N, P or neutral position, and the engine should be fully warmed up.
      • Enter the following menus: Powertrain / Engine / Data List / Injection Switching Status and confirm Injection Switching Status is OK.
    5. Read the value Short FT #1, Long FT #1 and Fuel Pump Duty.

      Result

      Item Proceed to
      Fuel Pump Duty Short FT #1 + Long FT #1
      10% to 40% -25% or less A
      10% to 40% -25% to +25% B
      10% to 40% +25% or more A

    Result: 

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    CHECK FOR INTERMITTENT PROBLEMS 

    (Refer to CHECK FOR INTERMITTENT PROBLEMS [06/2016 - ] )

  21. CHECK MISFIRE COUNT 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Start the engine.
    5. Enter the following menus: Powertrain / Engine / Active test / Control the Injection Way / Direct.
    6. Allow the engine to idle.
    7. Monitor all of the misfire count values that are displayed on the Techstream: Powertrain / Engine / Data List / Cylinder #1 Misfire Count to Cylinder #4 Misfire Count.

      If no misfire counts occur for any of the cylinders, perform the following procedure:

      1. Move the shift lever to D.
      2. Monitor all of the misfire rate values that are displayed on the Techstream.

        Result

        Misfire Count Proceed to
        No misfire counts, or misfire counts occur randomly in all cylinders A
        Misfire counts occur in particular cylinder B

    Result: 

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    See step  22

  22. INSPECT INJECTOR DRIVER (EDU) 
    1. Replace the injector driver (EDU) with known good ones from another vehicle.
      NOTE:

      Do not disconnect and reconnect the connectors with the ignition switch to ON, as the injector driver (EDU) may be damaged.

    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Clear the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    6. Turn the ignition switch off and wait for at least 30 seconds.
    7. Turn the ignition switch to ON and turn the Techstream on.
    8. Start the engine and warm it up.
    9. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    10. Enter the following menus: Powertrain / Engine / Trouble Codes.
    11. Read the pending DTCs.

      Result

      Result Proceed to
      P2096 and/or P2097 A
      DTC is not output B

    Result: 

    REPLACE FUEL PUMP ASSEMBLY (FOR HIGH PRESSURE) 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    END (INJECTOR DRIVER (EDU) IS DEFECTIVE) 

  23. CHECK FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION) 
    1. Check the injection volume (whether fuel volume is high or low, and whether injection pattern is poor).

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    NG 

    REPLACE FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION) 

    (Refer to REMOVAL [06/2016 - ] )

  24. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION) 
    1. Check the connection and terminal contact pressure of connectors and wire harness between the mass air flow meter and ECM (Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [06/2016 - ] ).

      HINT: 

      Repair any problems.

    Result: 

    NEXT 

    See step  25

  25. PERFORM CONFIRMATION DRIVING PATTERN 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON and turn the Techstream on.
    3. Clear the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    4. Turn the ignition switch off and wait for at least 30 seconds.
    5. Turn the ignition switch to ON and turn the Techstream on.
    6. Start the engine and warm it up.
    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    Result: 

    NEXT 

    See step  26

  26. CHECK WHETHER DTC OUTPUT RECURS (DTC P2096 AND/OR P2097) 
    1. Enter the following menus: Powertrain / Engine / Trouble Codes.
    2. Read the pending DTCs.

      Result

      Result Proceed to
      P2096 and/or P2097 A
      DTC is not output B

    Result: 

    END 

    Result: 

    See step  27

  27. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the mass air flow meter connector.
    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
      A33-22 (VG) - C16-5 (VG) Always Below 1 Ω
      A33-29 (E2G) - C16-4 (E2G) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      A33-22 (VG) or C16-5 (VG) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  28

  28. REPLACE MASS AIR FLOW METER 
    1. Replace the mass air flow meter (Refer to REMOVAL [06/2016 - ] ).

      HINT: 

      If the result of the inspection performed in step 8 indicated no problem, proceed to the next step without replacing the mass air flow meter.

    Result: 

    NEXT 

    See step  29

  29. PERFORM CONFIRMATION DRIVING PATTERN 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON and turn the Techstream on.
    3. Clear the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    4. Turn the ignition switch off and wait for at least 30 seconds.
    5. Turn the ignition switch to ON and turn the Techstream on.
    6. Start the engine and warm it up.
    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    Result: 

    NEXT 

    See step  30

  30. CHECK WHETHER DTC OUTPUT RECURS (DTC P2096 AND/OR P2097) 
    1. Enter the following menus: Powertrain / Engine / Trouble Codes.
    2. Read the pending DTCs.

      Result

      Result Proceed to
      P2096 and/or P2097 A
      DTC is not output B

    Result: 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    END