Got a '78 Vespa Bravo model with turn signals. When I bought the bike, the front ones were on but the rear ones were disconnected and the electronics in the rear metal "saddlebag" box looked not set up right.
I should get a picture of what's in that box, because I'm not sure what I'm looking at. I've looked at the diagram on page 23 of this . The two relevant parts look to be the Double Zener Diode and the Indicators Electronic Control Device. The two main components in this box are a large metal cylinder (a little bigger than a D-Cell battery) and a black square thing with four terminal posts coming out of it. There's also a red wire with a fuse inline that isn't connected to anything right now. The fuse especially leads me to believe that maybe there was a battery in this model. There's definitely not one in any of the diagrams in that manual, but that's for more recent models.
So the questions are: What are these two components (if they're the diode and control, which is which?) and do I need a battery? If I need a battery, how do I hook it up? Does it charge off the magneto?