Ground Circuit Inspection

IG "OFF".
Disconnect HO2S (B1/S1) connector.
Measure resistance between terminal 1 of HO2S (B1/S1) and chassis ground.
1. Specification : below 1 Ω
  
  Fig 1: Measuring Resistance Between Terminal 1 Of HO2S (B1/S1) And Chassis Ground
  Courtesy of HYUNDAI MOTOR CO.
Is the measured resistance within specification?
YES
1. Go to "COMPONENT INSPECTION " procedure.
NO
1. Repair or replace as necessary and then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.