Sorento V6-3.5L (2004)
Oxygen Sensor: Testing and Inspection
HEATED OXYGEN SENSOR (HO2S)
HO2S sensor senses the oxygen concentration in exhaust gas and converts it into a voltage which is sent to the ECU. For Zirconium type sensors, the
HO2S outputs about 1 V when the air fuel ratio is richer than the theoretical ratio, and outputs about 0 V when the ratio is leaner (higher oxygen
concentration in exhaust gas.). The ECU controls the fuel injection ratio based on this signal so that the air fuel ratio is maintained at the stoichiometric
ratio. HO2S has a heating element which ensures sensor performance during all driving conditions.
Circuit Diagram
1. If the HO2S is defective, abnormally high emissions may occur.
2. If the HO2S check results are normal, but the sensor output voltage is out of specification, check for the following items (related to air fuel ratio
