MY KITCHENAID DISH WASHER TOP SHELF IS NOT CLEANING AT ALL .

There may be something plugging up the arm that sprays over the dishes. And of course, I'm sure you know not to place items like bowls, pots, etc that will block the flow of water from the bottom sprays.

Although the bottom jets do most of the working cleaning the top items, the spray from above is vital. Take the stem pipe leadin from the top to the bottom off and separate the spray arms carefully. If you can, look throgh each end to make sure no deposits are in there.

Another way is to blow compressed air from the center stem down in the water supply unit. If food particles are there you'll see them.