Kia Optima: Intake Air Temperature Sensor (IATS). Description and OperationTo calculate precise air quantity, correction of the air temperature is needed because air density varies according to the temperature. So the ECM uses not only MAPS signal but also IATS signal. This sensor has a Negative Temperature Coefficient (NTC) Thermister and it's resistance changes in reverse proportion to the temperature.

Installation
Intake Air Temperature Sensor (IATS). SpecificationsInstrument Cluster. Schematic Diagrams
Circuit Diagram
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Replacement
1.
Remove the front wheel & tire.
Tightening torque:88.3
~ 107.9N.m(9.0 ~ 11.0kgf.m, 65.1 ~ 79.6lb-ft)
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Power Window Motor. Schematic Diagrams
Circuit Diagram
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