99 ply voy running lights/directionals

99 ply voy running lights/directionals are not always working when I need them. I've wiggled the fuse box and can get them on but they can't be trusted to stay on. I hear a clicking noise at the fuse box. And I think I located the small plug in box on the fuse box that is faulty. Do you know of a diagram that I can use to match it up with? How much should this black box plug in cost? Thank you