1500 just quit at 60 mph....

[vv0350]

My 2002 Nomad has about 5,500 miles...took off on a trip to Arkansas last week and about 65 miles from home and at about 60 mph...it just quit running...would NOT restart..it would turn over....pleanty of gas..
The bike is stock except for the power commander.....trailered it to the local shop which is a Honda shop and they looked at it..found a 15 amp fuse under the seat that had burned out..replaced it and during a test drive it blew again....and again...they think it is a bad short but where?? The shop mgr thinks it may be a bad power commander...but they just have no good clue for sure...any ideas..it has never done this before or given me a moments problem...always started right up quickly and run fine...