DIAGNOSIS A foreign object—like a piece of broken glass, a bone, or a cherry pit—has bypassed the filter and is caught in the wash impeller or pump.
FIX
- Immediately cancel the cycle and turn off the dishwasher.
- Remove the bottom rack and take out the entire filter assembly (twist and lift).
- Shine a flashlight into the pump sump at the bottom. Use needle-nose pliers to carefully remove any visible debris. Manually spin the impeller to check for obstruction.
IF THAT DIDN'T WORK The noise may be from the wash arm striking a tall, improperly loaded item like a utensil or cutting board. Reload to ensure nothing protrudes above the bottom of the upper rack.
HEADS UP Never let large food scraps enter the tub. The filter is coarse by design. Always scrape plates thoroughly. A persistent grinding after debris removal means the pump bearings are damaged and the circulation pump needs replacement.