JP1 Remotes

Have a faulty power inverter - ie one that produces 240V AC from 12V DC. Its a 1500W model and quite a beast inside (some 8 transformers and 16 MOSFETS).

I can't spot anything visibly faulty. Any thoughts on what I should be testing for? My only thought is to remove and test each of those 16 mosfets in turn.

Devices that use Mosfets can be very difficult to repair.
Many times the Mosfets are in parallel so you have to disconnect them to find a shorted one. You should check for open fuses or a thermal relay that did not reset At high current, those transformers can fail also but cannot be checked with simple ohm meters. You should also examine the solder connections carefully since high current can melt them or cause some arcing.

Due to the nature of inverters, I would limit repairs to things like open connections, fuses, relays and what are basically "mechanical" failures. Some of the electronic failure modes could be undervoltage or overvoltage conditions which could destroy the device connected to it.