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Home >> Nissan-Datsun >> 2023 >> 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 
    1. Refer to Component Inspection .

    Is the inspection result normal?

    YES>>

    INSPECTION END

    NO>>

    GO TO 6.

  6. REPLACE HEATED OXYGEN SENSOR 2 
    1. 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 
    1. Refer to Component Inspection .

    Is the inspection result normal?

    YES>>

    INSPECTION END

    NO>>

    GO TO 11.

  11. REPLACE HEATED OXYGEN SENSOR 2 
    1. 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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