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Home >> Hyundai >> 2011 >> Azera GLS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 3) >> DTC P0140: O2 Sensor Circuit No Activity Detected (Bank 1/Sensor 2) >> Inspection/Repair >> Component Inspection
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Component Inspection

  1. IG "OFF" and connect HO2S connector.
  2. Engine start.
  3. After warming-up, monitor signal waveform of HO2S with scantool.
    Fig 1: Checking Signal Waveform Of HO2S
    G07251413Courtesy of HYUNDAI MOTOR CO.
    Fig 2: Normal Waveforms Of Front HO2S (Upper) And Rear HO2S (Lower) (Chassis Ground Used)
    G07251414Courtesy of HYUNDAI MOTOR CO.
    Fig 3: Normal Waveforms Of Front HO2S (Upper) And Rear HO2S (Lower) (Sensor Ground Used)
    G07251415Courtesy of HYUNDAI MOTOR CO.
  4. Is the sensor switching properly?

    YES 

    • Go to "Check HO2S" as below.

    NO 

    • Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  1. IG "OFF" and disconnect HO2S connector.
  2. Check that the HO2S is securely installed.
  3. Check the HO2S for contamination or damage.
  4. Is the sensor normal?

    YES 

    • Substitute with a known - good ECM and check for proper operation. If the problem is corrected, replace ECM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
      NOTE: There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by ECM. Before or after testing ECM on the vehicle, use this function to reuse the ECM on the others

    NO 

    • Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.