Repairing a light on a string of mini-Christmas lights

Extend the life of your mini-light Christmas light strings with this simple replacement process.

Burned out mini-light
Burned out mini-light


The mini-Christmas lights are a simple two-part product. There is the base and a bulb. Bulbs are easy to replace when they burn out. Using finger power, pull out the faulty light and insert the replacement.

However, if you have run out of the spares that came with your light set, have lost them or only have replacement bulbs, the burned-out light can be repaired. ​All you need is a pocketknife or a fingernail to manipulate the wires and a replacement bulb.

Note: Replacement bulbs and base kits are sold in hardware and other stores. If you buy these, do not throw away the base of the burned-out light until you know the replacement bases will fit your light string. More on this later.


There are two types of mini Christmas light sets; those that will continue to operate when one or more bulbs are burned out, and those that don't.

This how-to will focus on the first type of mini-lights that remain in operation even with one or more individual lights burned out.

If you have a string of lights that goes dark when a bulb burns out, my advice is to buy a replacement set with LEDs. You will save a bit more energy and have the advantage of lights that will last for years and years. Otherwise, it is a real chore to locate the faulty lights!

Note: If all your lights are out, check the string's plug. Many are equipped with tiny fuses. If these blow, the whole string goes out. Spares are usually supplied. Replace the fuse and see if that fixes your issue.

Tip: How do you know if the fuse is blown? There are a couple of ways. These fuses are glass tubes with metal end caps. A thin wire inside the fuse carries the electricity to the lights. If this wire burns out, the fuse "blows" and breaks the electric circuit. This failure will break the wire and generally will blacken the glass tube. If you see one or both of these visual indicators, replace that fuse.

Not all mini-Christmas light bulbs are created equal

Unlike 120-volt bulbs that are manufactured with an industry-standard base, mini-light bulbs can have different bases. In the following image, you'll see two different bases. While they look similar, they are not interchangeable.

Two different mini-light bulb base styles

The bulb on the right is the one that has burned out and needs to be replaced. Notice the blackening of the glass that confirms bulb failure.

1. Check to see if you have assembled replacement bulbs on hand. If so, pop out the defunct bulb and pop in the replacement. All done!

2. If you don't have a complete replacement bulb or want a different color, remove the burned-out bulb by straightening the wires as shown below. and then pull the bulb out of its base. You can pitch the burned-out bulb.

Bulb contact wires straightened to allow removal

3. Repeat the process on the replacement bulb. Now you have two bases and two bulbs, one of which is no longer working.

Disassembled mini-lamp bulbs

4. Carefully insert the replacement bulb into the base of the bulb that burned out, gently fold the wires into place, making sure they are folded along the narrow edges.

5. Reinsert the assembled light and enjoy!

Replacement bulb installed in the proper base, lead wires ready to be folded over