SFI SYSTEM, Diagnostic DTC:P0140

DTC Code DTC Name
P0140 Heated Oxygen Sensor Circuit No Activity Detected (Bank 1 Sensor 2)

DESCRIPTION

Refer to DTC P0137 Click here.

DTC No. DTC Detection Condition Trouble Area
P0140

All of the following conditions are met (3 trip detection logic):


  • (1). 100 seconds have elapsed since No. 2 heated oxygen sensor dew point judgment* was completed.

  • (2). No. 2 heated oxygen sensor output voltage is between 1.25 and 3.5 V.

  • (3). Conditions (1) and (2) are met continuously for 5 seconds.

  • (4). Active air fuel ratio control is performed as follows after condition (3) is met:


    • (a) Pulse signal is applied to No. 2 heated oxygen sensor signal line.

    • (b) No. 2 heated oxygen sensor voltage is measured after pulse signal is applied.

    • (c) No. 2 heated oxygen sensor ) voltage after pulse signal applied is 2.8 V or higher.

    • (d) When condition (c) is met, steps (a) and (b) are repeated 2 more times.

  • (5). Average difference in No. 2 heated oxygen sensor output voltage when active air fuel ratio control is performed 3 times is 2.8 V or higher.

  • Open in No. 2 heated oxygen sensor circuit

  • No. 2 heated oxygen sensor

Tech Tips


  • *: Condensation may form in the exhaust pipes after the engine is started and before the exhaust system has warmed up. If condensation exists, the sensor element may be damaged if the No. 2 heated oxygen sensor heater is heated excessively. Therefore, the ECM will restrict the output of the No. 2 heated oxygen sensor heater until it determines condensation is not forming in the exhaust pipes. Dew point judgment is when the ECM judges that condensation is no longer forming.

  • The internal resistance of the No. 2 heated oxygen sensor cannot be measured using the tester.

WIRING DIAGRAM

Refer to DTC P0130 Click here.

CONFIRMATION DRIVING PATTERN

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

Tech Tips

DTC P0140 is detected when the vehicle is driven with a city driving pattern at an average vehicle speed of approximately 50 km/h (31 mph) for approximately 30 minutes.

CAUTION / NOTICE / HINT

Note


  • Perform idle learning after replacing the ECM Click here.

  • Inspection the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips


  • 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. Freeze frame data records the engine condition when malfunctions are detected. 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. READ VALUE USING GTS (O2S B1S2)


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / O2S B1S2.

    5. Warm up the heated oxygen sensor at an engine speed of 2500 rpm for approximately 90 seconds.

    6. Read the output voltage of the No.2 heated oxygen sensor during racing the engine.

      Standard voltage
      Fluctuates between less than 0.4 V and more than 0.55 V.

    NG

    CHECK HARNESS AND CONNECTOR (NO. 2 HEATED OXYGEN SENSOR - ECM) Click here

    OK

  2. CHECK WHETHER DTC OUTPUT RECURS (DTC P0140)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear DTCs Click here.

    5. Turn the ignition switch off and wait for 30 seconds.

    6. Turn the ignition switch to ON.

    7. Turn the GTS 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 and ECT / Trouble Codes.

    11. Read pending DTCs.

      Result
      Result Proceed to
      DTC P0140 is output A
      DTC is not output B

    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  3. REPLACE NO.2 HEATED OXYGEN SENSOR


    1. Replace the No.2 heated oxygen sensor Click here.


    NEXT

  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P0140)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear DTCs Click here.

    5. Turn the ignition switch off and wait for 30 seconds.

    6. Turn the ignition switch to ON.

    7. Turn the GTS 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 and ECT / Trouble Codes.

    11. Read the pending DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC P0140 is output B

    A

    END

    B

    REPLACE ECM Click here

  5. CHECK HARNESS AND CONNECTOR (NO. 2 HEATED OXYGEN SENSOR - ECM)


    1. Disconnect the B83 No.2 heated oxygen sensor connector.

    2. Disconnect the B97 ECM connector (for LHD).

    3. Disconnect the B101 ECM connector (for RHD).

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      B83-4 (OX1B) - B97-103 (OX1B) Always Below 1 Ω
      B83-3 (E1) - B97-135 (E12) Always Below 1 Ω
      B83-4 (OX1B) or B97-103 (OX1B) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      B83-4 (OX1B) - B101-103 (OX1B) Always Below 1 Ω
      B83-3 (E1) - B101-135 (E12) Always Below 1 Ω
      B83-4 (OX1B) or B101-103 (OX1B) - Body ground Always 10 kΩ or higher

    OK

    REPLACE NO. 2 HEATED OXYGEN SENSOR Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR