Older Maytag Arms Don't Spin

Dishwasher fills, heats, drains, and drys, but the arms don’t get water and spin. They both (top and bottom) swing freely. I inspected the wash impeller, and it’s fine.

Seems to me the next step is to check if water is getting to the wash impeller, but I don’t know how to check that.

Perhaps there are other items to check??

Thank you; steve