Pro Scrub option
If your KA dishwasher has the S type spray arm at the bottom, underneath it, it has a special device which turns to different positions and it´s when the wash arms or the pro scrub are activated. You must disassemble the wash arm base, remove the filter and everything to reach this kind of diverter. Its a red circle with 1 hole which turns to different positions to activate either the wash arms or the pro scrub. I believe it uses Frigidaire´s system that sprays one rack at a time, alternating between the middle and top with the bottom and the pro scrub device.
If your KA is still the 4 arm spray wash arm, at the back, where the pro scrub device is inserted, it has 2 stainless big marble kind balls, not noticeable without removing the screws and the plastic cover where the marbles are located, and by magnetism during the cycle they get repositioned making the water flow either to the pro scrub device or to the water column which makes water flow to the center and top wash arms, alternating between spray arms and the pro scrub.
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