Originally Posted by
KingAirDriver
Must have FMS as active Nav Source AND have APPR selected for the Nav-to-Nav transfer to occur.
Edited to add that the Loc will NOT auto-tune unless your Nav Source is FMS to begin with.
All true, as far as I can recall. Not many LOC-only approaches in my experience; they definitely fall into the "weird" category when it comes to making the FMS magic work.