My DMT400 is about two years old and functioned perfectly until last week. Once the wash cycle gets to the point it should drain, the dishwasher doesn't drain and the "Delicate" light flashes indicating a drain fault. If I cancel the wash and drain using the Heavy+Delicate switches, the pump works fine and drains the water. I disassembled the drain, cleaned everything and cleared the drain line with shop air. No issues there. Like I said, it fails to drain normally during the wash cycle but drains if I cancel the wash. Anyone see this before? I suspect that a sensor isn't working since the pump obviously works manually. I would appreciate any insight or knowledge with this issue. I'm not sure where the sensor is located or what it looks like.