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Home >> Nissan-Datsun >> 2021 >> Sentra SR >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2 Of 2) >> Components/Circuit Diagnosis >> A/F Sensor 1 Heater >> Component Inspection
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Component Inspection

  1. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER 
    1. Turn ignition switch OFF.
    2. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
    3. Check resistance between A/F sensor 1 terminals as per the following.

      A/F sensor 1

      Condition

      Resistance

      +

      -

      Terminal

      3

      4

      Temperature

      25 deg. C (77 deg. F)

      1.80 - 2.44 Ohms

      1

      Not existed

      2

      4

      1

      2

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    GO TO 2.

  2. REPLACE A/F SENSOR 1 

    Replace A/F sensor 1. Refer to Exploded View .

    CAUTION:
    • Discard any A/F 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 A/F sensor, clean exhaust system threads.

    INSPECTION END