Kia Optima: Input Speed Sensor. Description and OperationDescription
Input speed sensor is a vital unit that measures the rate of rotation of the input shaft inside the transaxle and delivers the readings to the TCM. The sensor provides critical input data that's used in feedback control, damper clutch control, gear setting control, line pressure control, clutch activation pressure control, and sensor fault analysis.

Installation
Input Speed Sensor. SpecificationsManual transaxle
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Removal
Replacing an on/off solenoid valve (SS-A, SS-B) does not require additional
hydraulic pressure adjustment; however, the hydraulic pre ...
Headrest
The rear seat(s) is equipped with headrests in the outboard seating positions
for the occupant's safety and comfort.
The headrest not only provides comfort for passengers, but also helps prot ...