Re: miele d/w g638 plus
Check base of machine.for water. Perhaps float switch has been activated? If no water in base check that float (polysterene) is seated correctly. Inlet/drain is the same led on these from memory, faults i’ve come across are something stuck in non-return valve or inlet (waterproof system) fault. The non-return valve is accessable from inside dishwasher, below filter, take off clip & look for something fouling impellor of of drain pump.
Hope this helps
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