Component Inspection

Check the Signal waveform of HO2S
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
  Courtesy of HYUNDAI MOTOR CO.
  
  Fig 2: Signal Waveform Data - Front HO2S (Upper) And Rear HO2S (Lower) (Chassis Ground)
  Courtesy of HYUNDAI MOTOR CO.
  
  Fig 3: Signal Waveform Data - Front HO2S (Upper) And Rear HO2S (Lower) (Sensor Ground)
  Courtesy of HYUNDAI MOTOR CO.
4. Is the sensor switching properly?
  YES
  - Go to 2.
  NO
  - Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to VERIFICATION OF VEHICLE REPAIR .
Check HO2S
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 .
    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 .