The purpose of the water pump in your dishwasher is to pump or draw water from the dishwasher during its various stages of the cleaning cycle. The ever-present use of the rinse pump in the washing process directly attributes to the failure of the pump over time. Two primary indicators of a dishwasher pump failure are your washers inability to effectively drain at the end of each wash cycle or noises emanating from the machine which might indicate worn or collapsed pump bearings; replacement is the preferred action under these circumstances.