Component Inspection

Visual Check (HO2S (S1) 

1. Ignition "OFF" and disconnect HO2S (S1) connector.
2. Check that HO2S (S1) is contaminated or damaged by foreign materials.

Check HO2S (S1) Performance 

1. Warm up the engine to normal operating temperature.
2. Connect VMI to KDS/GDS and select "Oscilloscope".
3. Connect Channel A positive probe to Pin No. 3 (Pumping Current) and Channel A negative probe to Pin No. 6 (Trim Resistor).
4. Connect Channel B positive probe to Pin No. 2 (Nernst Voltage) and Channel B negative probe to Pin No. 1 (Virtual Ground).
   Fig 1: Screen Display - Approx. 2000RPM (A) & Fuel Cut (B)

   Courtesy of KIA MOTORS AMERICA, INC.

   A: Approx. 2000rpm

   CH.1 - Pumping Current & Virtual Ground: - 0.5 to 0.4 V

   CH.2 - Nernst Voltage & Trim Resistor: -1.0 to -0.0 V

   B: Fuel Cut

   CH.1 - Pumping Current & Virtual Ground: Approx. 0.89V

   CH.2 - Nernst Voltage & Trim Resistor: Approx. 0.64V

Confirm Part Inspection 

1. Does the HO2S (S1) operate properly? (Check variation)

   YES 

   • Go to "Verification Of Repair " procedure.

   NO 

   • Carefully re-do this troubleshooting guide steps.
   • If problem still occurs, replace HO2S (S1) and then go to "System Inspection" procedure.