Bosch Washing Machine Grinding Due to Obstructed Drain Pump

To confirm this cause, access the service flap at the bottom front of the machine and unscrew the pump filter cover after draining residual water. Inspect the filter housing and the visible impeller blades for foreign objects such as coins, bra wires, buttons, or lint. Attempt to rotate the impeller manually; if it is stuck, restricted, or physically damaged, a foreign object is confirmed as the source of the obstruction.

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