Suzuki DF 90 Service Manual page 59

O SENSOR (Optional item)
2
The O sensor is installed in the exhaust manifold only when
2
the O feedback operation is performed.
2
This sensor is a zirconia element (platinum plated) which
changes output voltage depending on the oxygen concentra-
tion difference between its internal and external surfaces. The
voltage change reflects the concentration of the oxygen in the
exhaust gas and is used to perform the O
The terminal voltage change (0 – 1 V) is dependent on the
concentration of oxygen in the exhaust gas.
This detected voltage value therefore represents the oxygen
concentration. The terminal voltage decreases when the oxy-
gen concentration is high, and increases when it is low.
NOTE:
As the zirconia element is not conductive below 250°C, the O
sensor will not function properly until the engine is at normal
operating temperature.
NOTE:
Zirconia element
The zirconia element produces a potential difference (voltage)
when there is a difference in the oxygen concentration of the
gases which contact the two sides of the element.
Since the inner surface of the zirconia element (inside the sen-
sor) is exposed to atmospheric air and the outer surface ex-
posed to the exhaust gas, there is a difference in oxygen con-
centration on each side and thus a difference in the potential
generated.
feedback operation.
2
2
ENGINE CONTROL SYSTEM
Zirconia element
Housing
3-11