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Home >> Hyundai >> 2009 >> Santa Fe Limited, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (Fuel System (3.3L)) >> Heated Oxygen Sensor (HO2S) >> Function And Operation Principle
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Function And Operation Principle

Heated Oxygen Sensor (HO2S) consists of zirconium and alumina and is installed on upstream and downstream of the Manifold Catalyst Converter (MCC). After it compares oxygen consistency of the atmosphere with the exhaust gas, it transfers the oxygen consistency of the exhaust gas to the PCM. When A/F ratio is rich or lean, it generates approximately 1V or 0V respectively. In order that this sensor normally operates, the temperature of the sensor tip is higher than 370°C (698°F). So it has a heater which is controlled by the PCM duty signal. When the exhaust gas temperature is lower than the specified value, the heater warms the sensor tip.

Fig 1: Identifying Terminal And Sensing Element Of Heated Oxygen Sensor
G06217950Courtesy of HYUNDAI MOTOR CO.
Fig 2: Heated Oxygen Sensor Cutway View
G06217951Courtesy of HYUNDAI MOTOR CO.