Kia Optima: Heated Oxygen Sensor (HO2S). Description and OperationThe sensor must be hot in order to operate normally. To keep it hot, the sensor has a heater which is controlled by the ECM via a duty cycle signal. When the exhaust gas temperature is lower than the specified value, the heater warms the sensor tip.

Installation
Heated Oxygen Sensor (HO2S). SpecificationsCrash Pad. Components and Components Location
Components
1. Main crash pad assembly
2. Side speaker grille [LH]
3. Airbag blanking cover
4. Side speaker grille [RH]
5. Center speaker grille
6. Crash pad side cover [ ...
Replacement
1.
Disconnect the negative (-) battery
terminal.
2.
Using the screwdriver, remove
the side cover (A).
3.
Loosen the mounting screw and
the ...
Inspection
1.
Check signal waveform of Input
& output speed sensor using the GDS.
Specification: Refer to "Signal
Wave Form" section.
...