Sounds just like the issue that I had last summer and it turned out to be the voltage regulator on my 2007 FLHTC. I had the battery replaced, then the voltage regulator and things worked out well until I took it on a trip to the Ozarks and the light came on again, then went off. I stopped at Toad Suck Harley Davidson and they did a system check and said all is well. On the way back to Mt. View the light came back on and stayed on. I put it on a trailer and came back home. Turned out to be the new voltage regulator had went bad. Other post on this forum said there was a problem with some of the replacement regulators as well as the regulators on the newer scooters.

Happy Trail's