How Do You Fix Christmas Lights When Half of Them Are Out?

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Plugging in your holiday lights only to find that half of the strand has unlit bulbs is frustrating, but repairing the strand isn't always hard! In fact, whether you're using LED lights or traditional lights, there are a few easy ways to test and troubleshoot the strand of lights before you throw them away.

Don't let a bad strand bring down your holiday spirit. Follow these tips and see if you can restore light yourself.

Inspect Light Bulbs and Wiring

• Look for broken bulbs, as well as missing, damaged, or loose bulbs in the non-working section. Replacement bulbs are often included with the original product, so don't throw out those extra bulbs when you see them in your original packaging! Store them with your extra fuses, because you never know when you'll need them.

• Look for any exposed or frayed wires, or visible damage. If you find damaged sections, consider replacing the entire strand or use electrical tape to secure the affected area.

Use Replacement Bulbs and Light Sockets

• Use a bulb remover to swap individual bulbs between the working and non-working sections. If the issue moves with the bad bulb, you've identified a faulty bulb.

• If the problem persists in the same section, there may be an issue with the bulb socket or bulb wire.

Check for Corroded Light Sockets

• Corrosion in bulb seats can disrupt the electrical connection.

• Disconnect the lights from the electrical plug, then use a small wire brush or fine sandpaper to clean the inside of the sockets. You can use a cotton swab to gently clean out any loose residue in the bulb base.

Replace the Fuse

• If your Christmas lights have a fuse, check to see if it's blown. The fuse is typically located in the female plug.

• Replacement fuses are usually included in the manufacturer's packaging. Pro tip: Always keep those spare fuses with the replacement light backup bulbs they give you with the original product.

Use the "Twist and Push" Method

• With the lights unplugged from the power source, gently twist and push each light bulb in its socket to ensure a good connection.

• Poor contact can sometimes be the cause of half-out lights. Twisting them can help reset the light bulb in the bulb seat.

Apply Gentle Pressure

While the lights are plugged into the electrical outlet, apply gentle pressure to the wire between bulbs along the non-working section. Do they flicker? If it seems like there are broken wires, it might be a loose connection affecting the entire string that can be temporarily restored by applying pressure.

Create a New Circuit

LightKeeper Pro and LED Keeper are handy, easy-to-use special tools that successfully repair light strands. Trying a light tester might be a last resort this time, but next time you need to repair strings of lights, it might just be your go-to tool.

• LightKeeper Pro is a light repair tool for a conventional string of lights. It sends a pulse through the light set to help you find the bad bulb and fix the faulty shunt.

• LED Keeper is a special tool that fixes LED string lights with a broken circuit. It pierces the insulation of the wiring and connects the copper within the set wires on LED strings. Doing so creates a new electrical current that bypasses the damage in the wire. It does take a process of elimination to determine where the electrical circuit needs to be fixed, but it's a money saver.

Consider Section Replacement

If you can't identify the specific issue, consider replacing the non-working section with a new string of lights. This is practical if your lights are modular.