| TUCSON(LM) >2011 > G 2.4 DOHC > Fuel System > Engine Control System > Heated Oxygen Sensor (HO2S)>Description and Operation |

Description
Heated Oxygen Sensor (HO2S) consists of zirconium and alumina and is installed both upstream and downstream of the Manifold Catalytic Converter. It varies in accordance with the air/fuel ratio. The sensor must be hot in order to operate normally. To keep it hot, the sensor has a heater which is controlled by the ECM via a duty cycle signal. When the exhaust gas temperature is lower than the specified value, the heater warms the sensor tip.