I have bought a second hand part and have installed it when I try to solder the wires from the little square board the 3 wires on the old
replacement are different colors,
can some one please tell me what goes where also the little switch needs connecting up I do have a meter so I can do continuity tests
I just don't know enough to solder it properly here are some photos of my situation

the last time I tried to put a 9 v battery across one of my USA Train boards I blew it so I don't just want to try that method and I can't test what I don't understand