LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2019 >> Yaris LE >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Control System - Diagnostic Codes (5 Of 13) >> SFI System >> DTC P0140-00: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2) [08/2018 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0140-00: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2) [08/2018 - ]: Procedure

  1. VISUALLY INSPECT ECM CONNECTOR 
    1. Perform the ECM connector Inspection.
    2. Inspect the ECM connector pin type.

      Result

      Result
      200 Pin Type
      186 Pin Type

    Result: 

    186 Pin Type 

    See step  27

    Result: 

    200 Pin Type 

    See step  2

  2. PURPOSE: VERIFY CONNECTOR CONNECTIONS 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2) and Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)
    5. When the following parts are shaken, does the PID value include a PID item which has changed?
      1. HO2S
      2. ECM

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  26

    Result: 

    No 

    See step  3

  3. PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S 
    1. Connect the Techstream to the DLC3.
    2. Start the engine and idle it.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2).

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)
    5. Is the Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2) PID value normal?

      Refer to INSPECTION [08/2018 - ]

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  5

    Result: 

    Yes 

    See step  4

  4. PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S HEATER 
    1. Connect the Techstream to the DLC3.
    2. Start the engine and idle it.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2).

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
    5. Is the Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2) PID value normal?

      Refer to INSPECTION [08/2018 - ]

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  13

    Result: 

    Yes 

    See step  5

  5. PURPOSE: INSPECT HO2S CONNECTOR CONDITION 
    1. Switch the ignition off.
    2. Disconnect the HO2S connector.
    3. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    4. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  25

    Result: 

    No 

    See step  6

  6. PURPOSE: INSPECT ECM CONNECTOR CONDITION 
    1. Disconnect the ECM connector.
    2. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  24

    Result: 

    No 

    See step  7

  7. PURPOSE: INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND 
    1. Verify that the HO2S and ECM connectors are disconnected.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E4-2 - Body ground Always 10 kΩ or higher

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  23

    Result: 

    Yes 

    See step  8

  8. PURPOSE: INSPECT HO2S CIRCUIT FOR OPEN CIRCUIT 
    1. Verify that the HO2S and ECM connectors are disconnected.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E4-2 - A42-41 Always Below 1 Ω

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  22

    Result: 

    Yes 

    See step  9

  9. PURPOSE: INSPECT INSTALLATION OF HO2S 
    1. Verify the installation condition of the HO2S (installation angle, tightening torque value).

      Refer to INSTALLATION [07/2015 - ]

    2. Is the HO2S installed securely?

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  21

    Result: 

    Yes 

    See step  10

  10. PURPOSE: DETERMINE INTEGRITY OF HO2S 
    1. Reconnect all disconnected connectors.
    2. Inspect the HO2S.

      Refer to INSPECTION [08/2018 - ]

    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  20

    Result: 

    No 

    See step  11

  11. PURPOSE: VERIFY IF MALFUNCTION RELATED TO EMISSION SYSTEM AFFECTS HO2S SIGNAL 
    1. Verify the exhaust gas leakage from the exhaust system. (between A/F sensor and HO2S)
    2. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  19

    Result: 

    No 

    See step  12

  12. PURPOSE: VERIFY IF MALFUNCTION RELATED TO ENGINE COMPRESSION AFFECTS DIAGNOSTIC RESULTS 
    1. Inspect the engine compression.

      Refer to INSPECTION [07/2015 - 08/2019] , or refer to INSPECTION [08/2019 - ]

    2. Are compression pressures within specification?

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  18

    Result: 

    Yes 

    See step  13

  13. PURPOSE: DETERMINE INTEGRITY OF HO2S HEATER 
    1. Inspect the HO2S heater.

      Refer to INSPECTION [08/2018 - ]

    2. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  17

    Result: 

    No 

    See step  14

  14. PURPOSE: VERIFICATION OF VEHICLE REPAIR COMPLETION 
    1. Always reconnect all disconnected connectors.
    2. Clear the DTC from the ECM memory using the Techstream.

      Refer to CLEARING DTC [07/2015 - ]

      Powertrain > Engine > Clear DTCs 

    3. Implement the repeatability verification procedure.
    4. Perform the Pending Trouble Code Access Procedure.

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Trouble Codes 

    5. Is the PENDING CODE for this DTC present?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  16

    Result: 

    No 

    See step  15

  15. PURPOSE: VERIFY IF THERE IS ANY OTHER MALFUNCTION 
    1. Is any other DTC or pending code stored?

      Result

      Result
      Yes
      No

    Result: 

    No 

    DTC TROUBLESHOOTING COMPLETED. 

    Result: 

    Yes 

    GO TO THE APPLICABLE DTC INSPECTION. 

    1. Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2018 - 08/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [08/2019 - ]
  16. REPEAT THE INSPECTION FROM STEP 5. 
    1. If the malfunction recurs, replace the ECM.

      Refer to REMOVAL [07/2015 - ]

    2. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  17. REPLACE THE HO2S. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  18. REPLACE OR OVERHAUL THE ENGINE. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  19. REPAIR OR REPLACE THE MALFUNCTIONING PART ACCORDING TO THE INSPECTION RESULTS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  20. REPLACE THE HO2S. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  21. RETIGHTEN THE HO2S. 
    1. Refer to INSTALLATION [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  22. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN HO2S TERMINAL E4-2 AND ECM TERMINAL A42-41. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has an open circuit.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  23. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN HO2S TERMINAL E4-2 AND ECM TERMINAL A42-41. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has a short to ground.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  24. REPLACE THE ECM. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  25. REPLACE THE HO2S. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  26. REPAIR OR REPLACE THE APPLICABLE CONNECTOR PARTS. 
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  27. PURPOSE: VERIFY CONNECTOR CONNECTIONS 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2) and Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)
    5. When the following parts are shaken, does the PID value include a PID item which has changed?
      1. HO2S
      2. ECM

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  51

    Result: 

    No 

    See step  28

  28. PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S 
    1. Connect the Techstream to the DLC3.
    2. Start the engine and idle it.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2).

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2)
    5. Is the Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 2) PID value normal?

      Refer to INSPECTION [08/2018 - ]

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  30

    Result: 

    Yes 

    See step  29

  29. PURPOSE: VERIFICATION IF MALFUNCTION CAUSED BY HO2S HEATER 
    1. Connect the Techstream to the DLC3.
    2. Start the engine and idle it.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2).

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
      Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2)
    5. Is the Heated Exhaust Gas Oxygen Sensor Heater (bank 1, sensor 2) PID value normal?

      Refer to INSPECTION [08/2018 - ]

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  38

    Result: 

    Yes 

    See step  30

  30. PURPOSE: INSPECT HO2S CONNECTOR CONDITION 
    1. Switch the ignition off.
    2. Disconnect the HO2S connector.
    3. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    4. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  50

    Result: 

    No 

    See step  31

  31. PURPOSE: INSPECT ECM CONNECTOR CONDITION 
    1. Disconnect the ECM connector.
    2. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  49

    Result: 

    No 

    See step  32

  32. PURPOSE: INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND 
    1. Verify that the HO2S and ECM connectors are disconnected.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E67-1 - Body ground Always 10 kΩ or higher

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  48

    Result: 

    Yes 

    See step  33

  33. PURPOSE: INSPECT HO2S CIRCUIT FOR OPEN CIRCUIT 
    1. Verify that the HO2S and ECM connectors are disconnected.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E67-1 - A43-35 Always Below 1 Ω

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  47

    Result: 

    Yes 

    See step  34

  34. PURPOSE: INSPECT INSTALLATION OF HO2S 
    1. Verify the installation condition of the HO2S (installation angle, tightening torque value).

      Refer to INSTALLATION [07/2015 - ]

    2. Is the HO2S installed securely?

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  46

    Result: 

    Yes 

    See step  35

  35. PURPOSE: DETERMINE INTEGRITY OF HO2S 
    1. Reconnect all disconnected connectors.
    2. Inspect the HO2S.

      Refer to INSPECTION [08/2018 - ]

    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  45

    Result: 

    No 

    See step  36

  36. PURPOSE: VERIFY IF MALFUNCTION RELATED TO EMISSION SYSTEM AFFECTS HO2S SIGNAL 
    1. Verify the exhaust gas leakage from the exhaust system. (between A/F sensor and HO2S)
    2. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  44

    Result: 

    No 

    See step  37

  37. PURPOSE: VERIFY IF MALFUNCTION RELATED TO ENGINE COMPRESSION AFFECTS DIAGNOSTIC RESULTS 
    1. Inspect the engine compression.

      Refer to INSPECTION [07/2015 - 08/2019] , or refer to INSPECTION [08/2019 - ]

    2. Are compression pressures within specification?

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  43

    Result: 

    Yes 

    See step  38

  38. PURPOSE: DETERMINE INTEGRITY OF HO2S HEATER 
    1. Inspect the HO2S heater.

      Refer to INSPECTION [08/2018 - ]

    2. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  42

    Result: 

    No 

    See step  39

  39. PURPOSE: VERIFICATION OF VEHICLE REPAIR COMPLETION 
    1. Always reconnect all disconnected connectors.
    2. Clear the DTC from the ECM memory using the Techstream.

      Refer to CLEARING DTC [07/2015 - ]

      Powertrain > Engine > Clear DTCs 

    3. Implement the repeatability verification procedure.
    4. Perform the Pending Trouble Code Access Procedure.

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Trouble Codes 

    5. Is the PENDING CODE for this DTC present?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  41

    Result: 

    No 

    See step  40

  40. PURPOSE: VERIFY IF THERE IS ANY OTHER MALFUNCTION 
    1. Is any other DTC or pending code stored?

      Result

      Result
      Yes
      No

    Result: 

    No 

    DTC TROUBLESHOOTING COMPLETED. 

    Result: 

    Yes 

    GO TO THE APPLICABLE DTC INSPECTION. 

    1. Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2018 - 08/2019] , or refer to DIAGNOSTIC TROUBLE CODE CHART [08/2019 - ]
  41. REPEAT THE INSPECTION FROM STEP 30. 
    1. If the malfunction recurs, replace the ECM.

      Refer to REMOVAL [07/2015 - ]

    2. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  30

  42. REPLACE THE HO2S. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  43. REPLACE OR OVERHAUL THE ENGINE. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  44. REPAIR OR REPLACE THE MALFUNCTIONING PART ACCORDING TO THE INSPECTION RESULTS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  45. REPLACE THE HO2S. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  46. RETIGHTEN THE HO2S. 
    1. Refer to INSTALLATION [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  47. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN HO2S TERMINAL E67-1 AND ECM TERMINAL A43-35. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has an open circuit.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  48. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN HO2S TERMINAL E67-1 AND ECM TERMINAL A43-35. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has a short to ground.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  49. REPAIR OR REPLACE THE CONNECTOR AND/OR TERMINALS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  50. REPAIR OR REPLACE THE CONNECTOR AND/OR TERMINALS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

  51. REPAIR OR REPLACE THE APPLICABLE CONNECTOR PARTS. 
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  39

scientia non olet · About LEMON Manuals