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Home >> Hyundai >> 2004 >> Accent Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 2) >> DTC Troubleshooting Procedures >> DTC P0140: O2 Sensor Circuit No Activity Detected (Bank1/Sensor2) >> Monitor DTC Status
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Monitor DTC Status

This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.

  1. Connect scan tool to Data Link Connector (DLC).
  2. Warm up the engine to normal operating temperature.
  3. Monitor the "HO2S signal" parameter on the scan tool.
    Fig 1: Scan Tool Display (Current Data)
    G03851820Courtesy of HYUNDAI MOTOR CO.
    NOTE: The data shown above is only for reference and there may be a little difference actually.

    Service standard

    For front HO2S

    • When decelerating suddenly from 4000 RPM: 200mV or less
    • When engine is suddenly raced: 600~1000mV
    • 1500 RPM: The fluctuation between 400mV or less and 600~1000mV

      For Rear HO2S

    • Part load (Approx. 2000 RPM): 500~1000mV
  4. Is parameter displayed within specifications?

    YES 

    • Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared.

      Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.

    NO 

    • Go to "W/HARNESS INSPECTION" procedure.