Tracker 4x4 L4-1.6L VIN 6 (1995)
Oxygen Sensor: Description and Operation
Comp. Loc
Heated Oxygen Sensor Output Characteristics
HEATED OXYGEN SENSOR
DESCRIPTION
The Heated Oxygen Sensor (HO2S) is located in the exhaust manifold and detects the concentration of oxygen in the exhaust gases. It consists of
the zirconia element (with thin platinum surface coating) which generates voltage, a lead wire which draws out the voltage, and cover and housing
which protects the zirconia element from damage. The HO2S also incorporates a heater element. Refer to Chart C-1B Heated Oxygen Sensor
Check to verify that HO2S heater is working properly.
The zirconia element, by its property, generates the electromotive force when a difference in oxygen concentration exists between its faces. As its
temperature rises, the change of the electromotive force is amplified by catalytic reaction of the platinum. The HO2S makes use of this property.
As atmosphere is introduced into the HO2S, the inside of the zirconia element is exposed to the atmosphere and outside to exhaust gases. Thus, the
difference in concentration between the inside and the outside of the zirconia element varies with the oxygen concentration in the exhaust gases.
OPERATION