Definitely the pump and motor assembly. Easy to replace too. I didn’t even have to remove the washer. Everything can be done from inside and underneath. YouTube it.
My my machine was filling with water but it didn’t circulate the water. It did complete the cycle(even the detergent door opened), but it wasn’t washing dishes.
The part is a little pricey. $120-$170 depending on the model. But better than $400-$800 to replace. Plus easier than. Installing a new unit.
Thanks for the post!