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Home >> Nissan-Datsun >> 2021 >> Sentra S >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (1 Of 4) >> DTC/Circuit Diagnosis >> DTC P0136: O2 Sensor 2 Bank 1 >> DTC Diagnosis Procedure
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DTC Diagnosis Procedure

  1. INSPECTION START 
    1. Confirm the detected malfunction (A or B). Refer to DTC Description .

    Which malfunction is detected?

    A

    GO TO 2.

    B

    GO TO 7.

  2. CHECK HEATED OXYGEN SENSOR 2 CONNECTOR 
    1. Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
    2. Check that water is not inside connectors.

    There is no leakage.

    Is the inspection result normal?

    YES

    GO TO 3.

    NO

    Repair or replace malfunctioning part.

  3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
    4. Check the continuity between HO2S2 harness connector and ECM harness connector.

      HO2S2

      ECM

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E72

      1

      F25

      76

      Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace malfunctioning part.

  4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check the continuity between HO2S2 harness connector and ECM harness connector.

      HO2S2

      ECM

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E72

      2

      F25

      77

      Existed
    2. Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.

      HO2S2

      Ground

      Continuity

      Connector

      Terminal

      E72

      2

      Ground

      Not existed

      ECM

      Ground

      Continuity

      Connector

      Terminal

      F25

      77

      Ground

      Not existed
    3. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Repair or replace malfunctioning part.

  5. CHECK HEATED OXYGEN SENSOR 2 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 6.

  6. REPLACE HEATED OXYGEN SENSOR 2 

    Replace malfunctioning heated oxygen sensor 2. Refer to Exploded View .

    CAUTION:
    • Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
    • Before installing new oxygen sensor, clean exhaust system threads.

    INSPECTION END

  7. CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE 
    1. Start engine and warm it up to the normal operating temperature.
    2. Clear the mixture ratio self-learning value. Refer to Work Procedure .
    3. Run engine for at least 10 minutes at idle speed.

    Is the 1st trip DTC P0172 detected? Is it difficult to start engine?

    YES

    Perform trouble diagnosis for DTC P0172. Refer to DTC Description .

    NO

    GO TO 8.

  8. CHECK HEATED OXYGEN SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
    4. Check the continuity between HO2S2 harness connector and ECM harness connector.

      HO2S2

      ECM

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E72

      1

      F25

      76

      Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    Repair or replace malfunctioning part.

  9. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check the continuity between HO2S2 harness connector and ECM harness connector.

      HO2S2

      ECM

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E72

      2

      F25

      77

      Existed
    2. Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.

      HO2S2

      Ground

      Continuity

      Connector

      Terminal

      E72

      2

      Ground

      Not existed

      ECM

      Ground

      Continuity

      Connector

      Terminal

      F25

      77

      Ground

      Not existed
    3. Also check harness for short to ground and short to power.

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    Repair or replace malfunctioning part.

  10. CHECK HEATED OXYGEN SENSOR 2 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 11.

  11. REPLACE HEATED OXYGEN SENSOR 2 

    Replace malfunctioning heated oxygen sensor 2. Refer to Exploded View .

    CAUTION:
    • Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
    • Before installing new oxygen sensor, clean exhaust system threads.

    INSPECTION END

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