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Home >> Infiniti >> 2004 >> FX45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P0138 & P0158 Ho2S2 >> Component Inspection >> Heated Oxygen Sensor 2
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Heated Oxygen Sensor 2

With CONSULT-II 

  1. Turn ignition switch ON and select DATA MONITOR mode with CONSULT-II. See Figure .
  2. Start engine and warm it up to the normal operating temperature.
  3. Turn ignition switch OFF and wait at least 10 seconds.
  4. Start 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, and select HO2S2 (B1)/(B2) as the monitor item with CONSULT-II.
    Fig 1: Displaying Fuel Injection Active Test (CONSULT-II)
    G00344806Courtesy of NISSAN MOTOR CO., U.S.A.
  7. Check HO2S2 (B1)/(B2) at idle speed when adjusting FUEL INJECTION to +/-25%.
    Fig 2: Graphing Heated Oxygen Sensor 2 Voltage During Fuel Injection Adjustment At Ideal Speed
    G00344807Courtesy of NISSAN MOTOR CO., U.S.A.
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 using Oxygen Sensor Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

Without CONSULT-II 

  1. Start engine and warm it up to the normal operating temperature.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Start 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. Set voltmeter probes between ECM terminal 55 [HO2S2 (B1) signal] or 74 [HO2S2 (B2) signal] and ground.
    Fig 3: Checking Voltage At ECM Connector Terminal 55 Or 74
    G00344808Courtesy of NISSAN MOTOR CO., U.S.A.
  6. Check the voltage when revving up to 4,000 RPM under no load at least 10 times.

    (Depress and release accelerator pedal as soon as possible.)

    The voltage should be above 0.62V at least once during this procedure  .

    If the voltage is above 0.62V at step 6, step 7 is not necessary  .

  7. Keep vehicle at idling for 10 minutes, then check voltage. Or check the voltage when coasting from 80 km/h (50 MPH) in D position with OD OFF.

    The voltage should be below 0.48V at least once during this procedure  .

  8. 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 (using Oxygen Sensor Thread Cleaner tool J-43897-18 or J-43897-12) and approved anti-seize lubricant.
  9. If NG, replace heated oxygen sensor 2.