Had same problem last week on my 763F. The week prior to that the unit started up just fine. Then last week nothing.... just dead (no lights on bics, no click at starter, nothing, etc). Battery was three years old so I charged it for two days, BUT still nothing. Took it to local auto store for testing. Showed it was beyond dead, yikes. Although it did show 12 volts on a volt meter I had..... it was the battery being dead that caused my problem. I just replaced with a new one and all is fine. I hope your problem is as simple as that.