Ground Circuit Inspection

Ignition "OFF".
Disconnect HO2S connector.
Measure resistance between ground terminal of HO2S (B1/S1) harness connector and chassis ground.
Specification: Approx. 0Ω

Fig 1: Measuring Resistance Between Ground Terminal Of HO2S (B1/S1) Harness Connector & Chassis Ground
Courtesy of KIA MOTORS AMERICA, INC.
Is resistance within the specification?
NO
- Go to "SIGNAL CIRCUIT INSPECTION " procedure.
YES
- Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NOTE: HO2S must have a clean air reference to function properly. The air is obtained by way of the sensor wire (s). Do not attempt to repair the wire (s), connector, or the terminals.