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Home >> Nissan-Datsun >> 2021 >> Sentra S >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2 Of 2) >> Components/Circuit Diagnosis >> Ho2S2 >> Component Inspection
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Component Inspection

  1. INSPECTION START 

    Will CONSULT be used?

    YES

    GO TO 2.

    NO

    GO TO 3.

  2. CHECK HEATED OXYGEN SENSOR 2-1 

    SYMBOL With CONSULT

    1. Select "DATA MONITOR" mode of "ENGINE" using CONSULT.
    2. Start engine and warm it up to the normal operating temperature.
    3. Turn ignition switch OFF and wait at least 10 seconds.
    4. Restart engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
    5. Let engine idle for 1 minute.
    6. Select "FUEL INJECTION" in "ACTIVE TEST" mode of "ENGINE", and select "HO2S2 (B1)" as the monitor item with CONSULT.
    7. Check "HO2S2 (B1)" at idle speed when adjusting "FUEL INJECTION" to +/- 25%.
      GNSJSBIA3451Z-451Courtesy of NISSAN NORTH AMERICA, INC.

      SYMBOL

      : The voltage should be above 0.73 V at least on time.

      SYMBOL

      : The voltage should be below 0.18 V at least on time.

      "HO2S2 (B1)" should be above 0.73 V at least once when the "FUEL INJECTION" is +25%.

      "HO2S2 (B1)" should be below 0.18 V at least once when the "FUEL INJECTION" is +25%.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 6.

  3. CHECK HEATED OXYGEN SENSOR 2-2 

    SYMBOL Without CONSULT

    1. Start engine and warm it up to the normal operating temperature.
    2. Turn ignition switch OFF and wait at least 10 seconds.
    3. Restart engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
    4. Let engine idle for 1 minute.
    5. Check the voltage between ECM harness connector terminals under the following conditions.

      ECM

      Condition

      Voltage

      Connector

      +

      -

      Terminal

      F25

      77

      76

      Revving up to 4, 000 RPM quickly under no load at least 10 times. (Depress and release the accelerator pedal as quickly as possible.)

      The voltage should be above 0.73 V at least once during this procedure.

      The voltage should be below 0.18 V at least once during this procedure.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 4.

  4. CHECK HEATED OXYGEN SENSOR 2-3 

    SYMBOL Without CONSULT

    Check the voltage between ECM harness connector terminals under the following conditions.

    ECM

    Condition

    Voltage

    Connector

    +

    -

    Terminal

    F25

    77

    76

    Keeping engine at idle for 10 minutes.

    The voltage should be above 0.73 V at least once during this procedure.

    The voltage should be below 0.18 V at least once during this procedure.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 5.

  5. CHECK HEATED OXYGEN SENSOR 2-4 

    SYMBOL Without CONSULT

    Check the voltage between ECM harness connector terminals under the following conditions.

    CAUTION: Always drive vehicle at a safe speed.

    ECM

    Condition

    Voltage

    Connector

    +

    -

    Terminal

    F25

    77

    76

    Coasting from 80 km/h (50 MPH) in D position (CVT) or 4th position (M/T).

    The voltage should be above 0.73 V at least once during this procedure.

    The voltage should be below 0.18 V at least once during this procedure.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 6.

  6. REPLACE HEATED OXYGEN SENSOR 2 

    Replace 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