Chances are a wire got pimched or worn under the seat
(Another good reason to have a maintenance free battery so you don't have to take the seat off every week to check battery levels)
Since the tail light did come on once I'm betting you have a wire with some worn insulation under the seat.
BTW, the rear turnsignals are only tail lights/running lights if you convert them, they don't come that way stock.
Patriot Guard Rider
2000 VN750 Sere (Serendipity)
1990 GL1500 (Ole Blue)
1986 VN750 EVie (project bike, heavy custom)
VROC # 11628 / 25000-H
ARVROC # 12 Coordinator and Crowd Control
OKVROC # 18 (H)
TNVROC # 45 (H)