Control Circuit Inspection

Ignition "OFF".
Disconnect HO2S connector.
Ignition "ON"&Engine "OFF".
Measure voltage between Heater Control terminal of the HO2S harness connector and chassis ground.
Specification: 4-5V

Fig 1: Measuring Voltage Between Heater Control Terminal Of HO2S Connector And Chassis Ground (1 Of 2)
Courtesy of HYUNDAI MOTOR CO.

Fig 2: Measuring Voltage Between Heater Control Terminal Of HO2S Connector And Chassis Ground (2 Of 2)
Courtesy of HYUNDAI MOTOR CO.
Is voltage within the specification?
YES

Go to "COMPONENT INSPECTION " procedure.

NO

Repair 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.