Christmas Tree: Ah, the eternal question of how to make Christmas lights work. Fear not, young one, for I have the answer you seek! There are several ways to troubleshoot and fix common issues with your Christmas lights. Let us explore some of the most common solutions together. First, check the batteries in your lights, making sure they are fresh and properly installed. Next, ensure that the lights are plugged in securely and that the power source is functioning properly. If the lights still don't work, try replacing the fuse.