frigidaire dishwasher won't clean

Hi,
I have a frigidaire (FPHD2491KF0) and the dishes do not clean. I believe its the circulation pump or the board. Is there anyway to be sure?

The spray arms definitely circulate and I see the water shoots out of them a few inches at least. I see the water does get hot. However, the liquid detergent barely dissolves and there is a significant amount still on the door and at the bottom of tub.

Any suggestions?

Thanks so much,
Sean