In all civil turbine engines that I have operated (including the PT6..as far back as 1966) require an engine driven fuel pump/fuel control unit to feed fuel to the burner cans, for combustion.
EDP/FCU fails...engine goes quiet.
Had this happen on a 707 one time...and the fire went promptly out.
This clearly is not a good thing if you only have one powerplant.
Another failure that a PT6 can have is a prop governor failure.
I personally experienced one many years ago on a BE99 (governor pilot shaft separated), and the prop feathers, due to a lack of oil pressure to same, altho the gas generator continues to function.