Before ordering a replacement I had used the dishwasher's drain pump test mode. The pump vibrated but did not pump water. After the replacement arrived and I verified it was the right part, and removed the old drain pump. Upon disassembly, a small piece of plastic was lodged in the pump preventing rotation of pump gear. The plastic was not from the pump, the color was the same as the wash pump but I could not see any damage anywhere in the washer.