Component Inspection

1. Thoroughly check HO2S for contamination, deterioration or damage.
2. Is HO2S contaminated, deteriorated or damaged?

   YES 

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

   NO 

   • Go to "Check PCM" below.

The purpose of checking PCM is to determine whether there is any malfunction of PCM.

1. Ignition "OFF"
2. Disconnect HO2S sensor connector.
3. Connect scan tool and Engine "ON "
4. Select simulation function on scan tool.
5. Simulate voltage at terminal 2 of HO2S sensor signal connector.
6. Verify HO2S voltage to change while raising or lowering simulation voltage with scan tool within 0.2~0.8 V

   Specification: If the data is changeable as simulation voltage changes, it's OK

   Fig 1: Scan Tool Display (Simulation Voltage)

   Courtesy of HYUNDAI MOTOR CO.
7. Is HO2S signal value changed according to simulation voltage ?

   YES 

   • 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 

   • Substitute with a known-good PCM and check for proper operation. If the problem is corrected, replace PCM and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
     NOTE: It is not permitted to check the internal resistance of HO2S with analog multimeter.