Control Circuit Inspection

Check voltage
1. IG "OFF" & Disconnect HO2S (B1/S1) connector.
2. IG "ON".
3. Measure voltage between control terminal of HO2S (B1/S1) heater harness connector and chassis ground.
  Specification: Approx. 3.5V
  
  Fig 1: Measuring Voltage Between Control Terminal Of HO2S (B1/S1) Heater Harness Connector And Chassis Ground
  Courtesy of HYUNDAI MOTOR AMERICA
4. Is the measured voltage within specification?
  YES
  - Go to "COMPONENT INSPECTION " procedure.
  NO
  - Repair short to battery in HO2S (B1/S1) Heater control circuit and go to "VERIFICATION OF VEHICLE REPAIR " procedure.