I'm working on a faulty inverter, all the short mosfets have been replaced, but the fault alarm still sounds and there is no output voltage. Any help?

 

It could be difficult to say what the problem is with out a Schematic and without some general idea of what should be what volts and so on. It could be and most times found that it is a Cap that is the weak link. Most times removing the cap and testing them can tell the story. Not everyone has a ESR meter and some I think, "I feel it is cheaper" and just replace the caps and see if that makes it work again.

I would guess the Fuse was checked out to be ok.

A closer picture of the board and even the back side should be checked to make sure there is no broken traces It could be that easy if there was ever anything easy.

James