Component Inspection

Inspection Condition	(+) Probe		(-) Probe		Reference
Inspection Condition	Connector	Terminal	Connector	Terminal	Reference
Ignition "ON", engine "ON"	HO#4 (B2/S2) connector	1 (sensor signal)	Chassis ground	-	Figure below.
Ignition "ON", engine "ON"	HO#4 (B2/S2) connector	2 (sensor ground)	Chassis ground	-	Figure below.

Courtesy of KIA MOTORS AMERICA, INC.

Good

No Good

Carefully re-do this troubleshooting guide steps.
If no problems were found with the circuits or connectors, replace the HO2S (B2/S2) and go to "VERIFICATION OF REPAIR " procedure.