SFI SYSTEM, Diagnostic DTC:P0131

DTC Code DTC Name
P0131 Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 1)

DESCRIPTION

Refer to DTC P0130.

Click here

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0131

Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 1)

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

    1. Fuel-cut operation is not being performed.

    2. Purge control* of the catalyst is not being performed.

    3. Heated oxygen sensor (sensor 1) output voltage is less than 0.06 V.

    4. Conditions (a), (b) and (c) are met for 5 seconds or more.

    5. Active air-fuel ratio control is performed as follows after condition (d) is met:

      1. Pulse signal is applied to heated oxygen sensor (sensor 1) signal line.

      2. Heated oxygen sensor (sensor 1) voltage difference before and after applying pulse signal is calculated.

      3. Steps (1) and (2) are repeated 2 more times.

    7. Average difference in heated oxygen sensor (sensor 1) voltage when active air-fuel ratio control is performed 3 times is less than 0.015 V.

  • Heated oxygen sensor (sensor 1) circuit

  • Heated oxygen sensor (sensor 1)

  • ECM

Comes on

DTC stored
Tip:

*: In order to purge oxygen adsorbed to the TWC, the stoichiometric ratio is controlled to rich side.

WIRING DIAGRAM

Refer to DTC P0130.

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CAUTION / NOTICE / HINT

Note:

After replacing the ECM, perform idle learning.

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Tip:

  • 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. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0131)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Read the pending DTCs.

      Powertrain > Engine and ECT > Trouble Codes

      Result

      Result

      Proceed to

      DTC P0131 is output

      A

      DTC P0131 and other DTCs are output

      B
      Tip:

      If may DTCs other than P0131 are output, troubleshoot shoes DTCs first.

    B

    GO TO DTC CHART

    Click here

    A

  2. INSPECT HEATED OXYGEN SENSOR (SENSOR 1)

    1. Inspect the heated oxygen sensor (sensor 1).

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE HEATED OXYGEN SENSOR (SENSOR 1)

    Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR (SENSOR 1) - ECM)

    1. Disconnect the heated oxygen sensor (sensor 1) connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B4-4 (OX1A) - B31-126 (OX1A)

      Always

      Below 1 Ω

      B4-2 (HT1A) - B31-25 (HT1A)

      Always

      Below 1 Ω

      B4-3 (E1) - B31-125 (E11)

      Always

      Below 1 Ω

      B4-4 (OX1A) or B31-126 (OX1A) - Body ground

      Always

      10 kΩ or higher

      B4-2 (HT1A) or B31-25 (HT1A) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE HEATED OXYGEN SENSOR (SENSOR 1)

    1. Replace the heated oxygen sensor (sensor 1).

      Click here

    Result

    Proceed to

    NEXT
    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC P0131)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

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

    6. Start the engine and warm it up.

    7. Turn the GTS on.

    8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    9. Read the pending DTCs.

      Powertrain > Engine and ECT > Trouble Codes

    Result

    Result

    Proceed to

    DTC P0131 is output

    A

    DTCs are not output

    B
    A

    REPLACE ECM

    Click here

    B

    END