Section 03-14: Engine Controls, Electronic
1996 F-150, F-250, F-350, F-Super Duty Series and Bronco Vehicles Workshop Manual
DESCRIPTION AND OPERATION

Heated Oxygen Sensor (HO2S)

Gasoline Engines

The heated oxygen sensors (HO2S) (9F472) react with the oxygen in the exhaust gases and will generate a voltage. A low voltage indicates too much oxygen or a lean condition. A high voltage indicates not enough oxygen or a rich condition. The location and number of heated oxygen sensors will vary with engine size and vehicle application. Refer to the Removal and Installation portion of this section for illustrations showing oxygen sensor installation views.