It indicates low fuel. The Magna has a smallish upper fuel tank that empties into a lower tank that has an electric fuel pump. No way to tell how much fuel you have without the fuel light. I do not remember the tank to tank range,but I only get about 30MPG.
Look at the gauges when you key the bike on as I am fairly certain that there is also an oil pressure light.
BTW,take good care of your fuel with Sta-Bil and keep it full. Some of the fuel system parts are becoming unobtanium. Carb removal is a nightmare,so also a reason to take care of things.
But what a motorcycle! 80 horsepower that goes berserk at RPM of 6500+ They can be as smooth as you want as well, but my main problem is wanting to ride too fast.
It is supposed to only light when the reserve tank is hit. It is a low fuel warning light. When you turn the bike on it will light up but after a second it should turn off if you have enough gas already.
The sensor is probably pooched. They can be repaired.
The V65 has an electric fuel pump but I am pretty sure the smaller ones were gravity fed.