Replace the fuse Most new packs of Christmas lights come with a replacement fuse—which should give you a clue as to how common fuse problems are with these things.

Newer LED lights can cast a strange glow, so try to plug in your light string before buying it. It's always a good idea to keep extra bulbs and fuses in a well-marked box where you store your lights.

"Further, do not use foil or other metallic objects in place of busted light bulbs in a Christmas light string. In replacing light bulbs or fuses, make sure to unplug the Christmas lights first.