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 GDS.
   Fig 1: Checking Signal Waveform Of HO2S

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 2: Screen Display - Normal Waveforms Of Upstream HO2S (Upper) And Downstream HO2S (Lower) (Chassis Ground)

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 3: Screen Display - Normal Waveforms Of Upstream HO2S (Upper) And Downstream HO2S (Lower) (Sensor Ground)

   Courtesy of HYUNDAI MOTOR AMERICA
4. Is the sensor switching properly?

   YES 

   • Check HO2S for poor connection/installation or damage. If O.K., Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair " procedure 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 below.