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