I posted this in the mechanics subforum but was directed here.

A previous owner of this bike put a sidewall dynamo and light on it, but it is not connected. I have never seen one of these (up close) and have no idea how to connect it. Like absolutely no idea, so I apologize for being completely clueless. I'm attaching some pictures and I hope someone can point me in the right direction. The dynamo has 4 connection points and a short wire. The light has 4 connection points, 2 labeled IN (+ and -) and 2 labeled OUT (+ and -.) Then there's a double wire (one black and one with a white stripe) to attach the light to the dynamo. My attempts to connect this have so far not worked ... for all I know maybe the light doesn't even work. How do I hook this thing up? It would be cool if I could actually get it working.

By the way this seems to be instructions for this light but all it says is "The cable coming from the dynamo must be connected to the terminals of the headlight that are marked “in”" (which is not that helpful)
http://en.bumm.de/fileadmin/user_upl...C_Lyt_2012.pdf