Oxygen Sensor: Description and Operation

Fig. 6 Oxygen Sensor (Typical):

The exhaust oxygen sensor is located in the exhaust system and monitors oxygen content in the exhaust gas stream. The oxygen content of the exhaust gas reacts with the oxygen sensor to produce a voltage output, Fig. 6. By monitoring the oxygen sensor output voltage, the ECM can determine the amount of oxygen in the exhaust gas and adjust the air/fuel mixture accordingly.