yes my fueler had loose connections to the fueler unit (broken wires) in my case the unit would sometimes work then not work causing the engine to change in character. then it stopped working all together causing the bike to revert to standard map leading to really really lean mix as I've a free flow a/c and pipes.
So as far as i know if the units fail completely the bike just reverts to factory map.
As for the dealer........ they ofc wouldent touch it as they dident fit it. so i had to ride it back to the shop i brought the bike from, 150 mls away, and they replaced the unit.