IWL16 is a Phase 7 machine, which does not have an OOB switch. It uses "bump detection software" that does not involve a physical switch. The tube on the board is for the water level pressure sensor and has nothing to do with the machine being dead. The other end of it connects to a small air dome on side of the tub. The wire inside doesn't connect to anything, presumably it's to add stability and help prevent the tube from kinking at the board end.

A dead machine can only be caused by a bad controller board, or possibly the display board but that's rare). Have you examined the pump for evidence of leaking? Pumps leaking/wet over a period of time are the primary cause of a zapped board. There's typically a fuse on the board that blows. It's soldered to the board and not intended to be replaced separately because the premise is that if the fuse blew then some other electronic components on the board were probably damaged. However, I've had contact with a couple DIYers who did replace the fuse, one successful and one apparently did have further trouble with the board.

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