Having looked into a problem like this, I can say there seem to be two main failures that lead to what you see:
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Having looked into a problem like this, I can say there seem to be two main failures that lead to what you see: 1) the rectifier is damaged, which also blows the fuse, and both parts need to be replaced. or 2) those parts aren’t blown and unless you are lucky and have a visibly damaged other part, there isn’t much help (though there does seem to be a theme of pulsing voltages on the DC outputs, there is no root cause or solution known)