Under the seat is a box below the toolkit. In there you find a starter

relay sitting in a terminal. . . .check all wires going into it from below.
I had the same problem on my 2004 a while back and found one of the wires corroded and broken. . . .after I replaced the connector my bike was just fine...........the cause of the heavy corrosion was the little drain hole of the plastic box was jammed with shit and the water was sitting in there. . . .I mounted a mud sling later and check the hole sometimes to make sure it stays open. . . . .hope it helps