“Help! My Christmas lights set has gone completely out!”
If an entire set of mini lights has gone out, more than likely, you’ve blown a fuse. This commonly happens when too many mini lights sets are connected in series.
In most sets of Christmas lights, there are one or two fuses located in the male plug. If too many sets are connected in series, they will draw more current than the sets can handle safely and the fuses will “blow”. Unplugging the sets and replacing the fuses should restore them.
Replacement fuses are usually packaged with replacement bulbs in tiny little bags and taped to the Christmas light strings near the male plug. Be sure to collect these little bags into labeled bags for the future.
Using a small short flathead screwdriver, slide back a little door on the male plug and use a small flathead screwdriver – the kind that is used to open little screws on battery doors – to gently pry out the burned-out fuse and gingerly install a fresh fuse.
If replacing the fuse does not solve the “lights-out” issue, an alternative issue might be an unseated bulb. So, if your fuses are OK, look for a damaged bulb base or unseated bulb. If a bulb is damaged, use one of the included extra bulbs as a replacement.
Here is a quick video on where to find and how to replace the fuse in your set of mini lights. We’ve also included a quick blog post about stringing too many Christmas lights together.
Originally published on November 4, 2011 3:30 pm. Updated October 5, 2022.