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Home >> Nissan-Datsun >> 2021 >> NV2500 HD S >> Repair and Diagnosis >> External Pages >> Different car >> Section 399 (Engine Control System (DTC/Circuit Diagnosis) (14 Of 17)) >> DTC/Circuit Diagnosis >> DTC P2270: Ho2S2 >> Diagnosis Procedure

Diagnosis Procedure

WARNING: This page is about a different car, the 2019 Infiniti QX60. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECTION START 

    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 GROUND CONNECTION 
    1. Turn ignition switch OFF.
    2. Check ground connection E9. Refer to Ground Inspection in Circuit Inspection .

    Is the inspection result normal?

    YES

    GO TO 3.

    NO

    Repair or replace ground connection.

  3. CHECK HO2S2 GROUND CIRCUIT 
    1. Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
    2. Disconnect ECM harness connector.
    3. Check the continuity between HO2S2 harness connector and ECM harness connector.

      DTC

      HO2S2

      ECM

      Continuity

      Bank

      Connector

      Terminal

      Connector

      Terminal

      P2270

      1

      F71

      4

      F79

      99

      Existed

    4. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair open circuit, short to ground or short to power in harness or connectors.

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

      DTC

      HO2S2

      ECM

      Continuity

      Bank

      Connector

      Terminal

      Connector

      Terminal

      P2270

      1

      F71

      3

      F79

      110

      Existed

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

      DTC

      HO2S2

      --

      Continuity

      Bank

      Connector

      Terminal

      P2270

      1

      F71

      3

      Ground

      Not existed

      DTC

      ECM

      --

      Continuity

      Bank

      Connector

      Terminal

      P2270

      1

      F79

      110

      Ground

      Not existed

    3. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Repair open circuit, short to ground or short to power in harness or connectors.

  5. CHECK HO2S2 CONNECTOR FOR WATER 

    Check connectors for water.

    Water should not exist.

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    Repair or replace harness or connectors.

  6. CHECK HEATED OXYGEN SENSOR 2 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    Replace malfunctioning heated oxygen sensor 2. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST .

  7. CHECK GROUND CONNECTION 
    1. Turn ignition switch OFF.
    2. Check ground connection E9. Refer to Ground Inspection in Circuit Inspection .

    Is the inspection result normal?

    YES

    GO TO 8.

    NO

    Repair or replace ground connection.

  8. CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE 
    1. Clear the mixture ratio self-learning value. Refer to Description .
    2. Run engine for at least 10 minutes at idle speed.

    Is the 1st trip DTC P0172 or P0175 detected? Is it difficult to start engine?

    YES

    Perform trouble diagnosis for DTC P0172, P0175. Refer to DTC Index .

    NO

    GO TO 9.

  9. CHECK HO2S2 GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect heated oxygen sensor 2 harness connector.
    3. Disconnect ECM harness connector.
    4. Check the continuity between HO2S2 harness connector and ECM harness connector.

      DTC

      HO2S2

      ECM

      Continuity

      Bank

      Connector

      Terminal

      Connector

      Terminal

      P2270

      1

      F71

      4

      F79

      99

      Existed

    5. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    Repair open circuit, short to ground or short to power in harness or connectors.

  10. CHECK HO2S2 INPUT SIGNAL CIRCUIT 
    1. Check the continuity between HO2S2 harness connector and ECM harness connector.

      DTC

      HO2S2

      ECM

      Continuity

      Bank

      Connector

      Terminal

      Connector

      Terminal

      P2270

      1

      F71

      3

      F79

      110

      Existed

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

      DTC

      HO2S2

      --

      Continuity

      Bank

      Connector

      Terminal

      P2270

      1

      F71

      3

      Ground

      Not existed

      DTC

      ECM

      --

      Continuity

      Bank

      Connector

      Terminal

      P2270

      1

      F79

      110

      Ground

      Not existed

    3. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 11.

    NO

    Repair open circuit, short to ground or short to power in harness or connectors.

  11. CHECK HEATED OXYGEN SENSOR 2 

    Refer to Component Inspection .

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    Replace malfunctioning heated oxygen sensor 2. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST .