stern light wire wiring

So I installed a new light base for the stern and for some reason my new light is not working. I also don't know how to figure out if there's any power going back there which I don't think there is but I don't know where to trace this wire. It's gray and white. Hopefully I got it on this picture...

Hi there everyone, I recently acquired the perfect boat for my family, but have learned that it is not quite perfect (of course). Our model has the watersports tower option that has a stern light mounted on top. I discovered that the light does not work, so I traced the wires and found them...