Component Inspection

Visually/physically inspect the air leakage in exhaust system.
Visually/physically inspect the TWC and HO2S (B1/S2) for contamination, deterioration, or damage.
Was a problem found in any of the above areas?
YES
- Replace or repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Go to next step as below.
Warm up the engine to normal operating temperature and check that HO2S signal is active.
Connect scan tool and monitor the "O2 SNSR VOLT.(B1/S2)" parameter on the scan tool data list.
Test Condition: Ignition "ON" and Engine "ON" and In Idle ("Closed Loop") condition.

Fig 1: Scan Tool Display - O2 SENSOR VOLTAGE
Courtesy of KIA MOTORS AMERICA, INC.
Is sensor data near the specified value?
YES
- Check for poor connection between PCM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Check HO2S (B1/S2) for contamination, deterioration, or damage. Substitute with a known-good HO2S (B1/S2) and check for proper operation. If the problem is corrected, replace HO2S (B1/S2) and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.