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. SpecificationsFront Impact Sensor (FIS). Components and Components Location
Components
...
Replacement
1.
Loosen the wheel nuts slightly.
Raise the vehicle, and make sure it is securely supported.
2.
Remove wheel nuts, front wheel
and tire from front hub.
...
Removal
Parking Assist Sensor
1.
Disconnect the negative (-) battery
terminal.
2.
Remove the rear bumper.(Refer
to the BD group - "Rear bumper")
3.
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