Its 99.9{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} probable that the flow rate meter has failed . This is a component that measures the amount of water flowing into the machine telling the control board how long to fill for. When this fails , you get a constant fill/drain cycle going on.
The flow rate meter ( Impellor jug ) is white circular object between the end of the inlet hose and the water matrix on the LHS . Yu will need to remove the LHS panel to access and the part you require is 424099 from BSH home appliances .
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