Hyundai Elantra AD Quiz
Engine Control System/Fuel System

Heated Oxygen Sensor (HO2S) Description and Operation

In this manual: Engine Control System/Fuel System
General Information — 9Engine Mechanical System — 84Engine Electrical System — 60Emission Control System — 24Engine Control System/Fuel System — 90Automatic Transmission — 92Drive Shaft and Axle — 20Suspension System — 31Steering — 20Restraints — 50Brake System — 63Body (Interior and Exterior) — 214Body Electrical System — 221Heating, Ventilation, and Air Conditioning — 71
~1min read

Description

The Heated Oxygen Sensor (HO2S) consists of zirconia and alumina and is installed both upstream and downstream of the catalytic converter. Its output changes according to the air-fuel ratio. For proper operation the sensor must be hot. To keep it hot, the sensor has a heater which is controlled by the ECM through a duty cycle signal. If the exhaust gas temperature is below the specified value, the heater warms the sensor tip.

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