Kia Optima: Tire ReplacementIf the tire is worn evenly, a tread wear indicator will appear as a solid band 1/2 inch wide (12.7 mm) across the the tread. This shows there is less than 1/16 inch (1.6 mm) of tread left on the tire. Replace the tire when this happens.
Do not wait for the band to appear across the entire tread before replacing the tire.

Tire Rotation
Compact Spare Tire ReplacementEngine Oil. Repair procedures
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Seat Belt Buckle Switch (BS). Description and Operation
Description
The SRSCM shall monitor the status of the driver and front passenger seat belt buckle.
The SRSCM provides one pin each for the driver and front passenger seat belt buckle
status input ...
Before Starting
Close and lock all doors.
Position the seat so that all controls are easily reached.
Adjust the inside and outside rearview mirrors.
Be sure that all lights work.
Check all gauges.
Check ...