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Home >> Infiniti >> 2015 >> QX60 Base, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Wiring Diagrams And Diagnostic Trouble Codes (DTCS) U0101-P0161) (Except Hybrid) >> DTC/Circuit Diagnosis >> DTC P0139, P0159: O2 Sensor 2 Circuit Slow Response >> Component Inspection >> Diagnostic Test
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Diagnostic Test

  1. INSPECTION START

    Will CONSULT be used?

    Will CONSULT be used?

    YES 

    GO TO STEP 2. 

    NO 

    GO TO STEP   3 . 

  2. CHECK HEATED OXYGEN SENSOR 2

    G-20With CONSULT: 

    1. Turn ignition switch ON and select "DATA MONITOR" mode with 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. 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.
    7. Check "HO2S2 (B1)/(B2)" at idle speed when adjusting "FUEL INJECTION" to +- 25%.
      Fig 1: Fuel Injection Voltage Graph
      G08968446Courtesy of NISSAN NORTH AMERICA, INC.
      SMALL-A : The voltage should be above 0.72 V at least on time.
      SMALL-B : The voltage should be below 0.27 V at least on time.

      "HO2S2 (B1)/(B2)" should be above 0.68 V at least once when the "FUEL INJECTION" is + 25%. 

      "HO2S2 (B1)/(B2)" should be below 0.18 V at least once when the "FUEL INJECTION" is - 25%. 

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    Replace malfunctioning heated oxygen sensor 2. Refer to REMOVAL AND INSTALLATION (BANK 2) , REMOVAL AND INSTALLATION (BANK 1) .

  3. CHECK HEATED OXYGEN SENSOR 2-I

    G-21Without 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. 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. Check the voltage between ECM harness connector terminals under the following conditions:
      ECM Condition Voltage
      Connector + -
      Terminal
      F78 32 35 Revving up to 4, 000 RPM under no load at least 10 times The voltage should be above 0.72 V at least once during this procedure.
      The voltage should be below 0.27 V at least once during this procedure.
      41

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    GO TO STEP 4. 

  4. CHECK HEATED OXYGEN SENSOR 2-II

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

    ECM Condition Voltage
    Connector + -
    Terminal
    F78 32 35 Keeping engine at idle for 10 minutes The voltage should be above 0.72 V at least once during this procedure.
    The voltage should be below 0.27 V at least once during this procedure.
    41

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    GO TO STEP 5. 

  5. CHECK HEATED OXYGEN SENSOR 2-III

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

    ECM Condition Voltage
    Connector + -
    Terminal
    F78 32 35 Coasting from 80 km/h (50 MPH) with selector lever in the D position The voltage should be above 0.72 V at least once during this procedure.
    The voltage should be below 0.27 V at least once during this procedure.
    41

    Is the inspection result normal?

    YES 

    INSPECTION END

    NO 

    Replace malfunctioning heated oxygen sensor 2. Refer to REMOVAL AND INSTALLATION (BANK 2) , REMOVAL AND INSTALLATION (BANK 1) .

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