Of a machine, to be acting strangely or malfunctioning. Our washer has gone phut, so I'm on my way to the laundromat.
go phutfail to work properly or at all. informal
Phut is usually considered to be imitative of a dull, abrupt sound, like that made by a rifle or a machine breaking down. In fact, its earliest recorded use is by Rudyard Kipling in the late 19th century, and the context makes it likely that it was an Anglo-Indian word from Hindi and Urdu phatna meaning ‘to burst’.