How to fix christmas lights

How to fix christmas lights

Wondering how to fix Christmas lights? The illuminations for your home are part of the magic of the season, and discovering a problem with a bulb, a section, or the whole string will definitely leave it short on festive sparkle.

But the good news is that fixing fairy lights is a task you can tackle yourself so you can enjoy Christmas lighting ideas all around your home without having to replace the sets you already own.

We’ve put together a step-by-step guide so you know how to fix Christmas tree lights, and you’ll find top advice from the experts here, too.

How to fix Christmas lights

It’s a problem many of us have encountered. The functioning string of Christmas fairy lights you tidied away last year doesn’t work at all this year. Or maybe it’s that individual bulbs aren’t working now you go to hang the string as part of your holiday decor. Either way, there’s no need to give up before you’ve even started if you know how to fix Christmas lights.

You will need:

  • Small screwdriver available at Amazon

1. Inspect the Christmas lights

This is an important step that should be carried out before you even plug in your Christmas lights, but it is important as it could reveal a problem that needs fixing before you try switching the lights on.

You’re looking for any issues such as cracks in the insulation of the wires or, worse, wires that are exposed. Take a look at the state of the plug as well.

Found problems like these? Then you should discard the string and replace it with a new set.

2. Check the fuse

Plug the Christmas lights in. Entire string not working? Check the fuses in the plug, and be aware that there might be two of them.

Using a small screwdriver, remove a blown version if this is the issue, and replace it with a new one. Make sure its rating is as shown on the plug.

3. Look for faulty bulbs

Wondering how to fix Christmas lights if the problem is that one bulb isn’t working?

First of all, check the problem isn’t a loose connection. Simply twist the bulb; if it moves then this may have been the issue and you can plug the string in to check if it now works.

If that wasn’t the problem, replace the bulb. Make sure you follow the rules on Christmas light safety and do so with a bulb with the correct voltage rating.

3. Mend a section of Christmas lights

Perhaps the problem is that a whole section of the lights isn’t working? ‘Christmas light strings share a circuit so when one isn’t firmly attached, it throws out the entire circuit which means the others aren’t going to light up either,’ explains Andre Kazimierski, CEO, Improovy (opens in new tab) .

‘Strings of at least 50 lights typically have between two to four circuits, which is why the whole string doesn’t go out.

‘Usually the culprit is a bulb that’s come unseated from contact with the circuit,’ he explains. ‘This is easy to fix, but you need to be careful. It may be tempting to do this while the lights are plugged in to get quick feedback on what you’re doing, but you could electrocute yourself if you do this. Unplug the lights and check each bulb in the set that isn’t working. Make sure they’re screwed in tightly then plug the lights in again.’

4. Deal with a faulty shunt

The problem with Christmas lights may be a faulty shunt. Use the Christmas light repair tool (opens in new tab) available at Amazon as directed in the instructions. Test the lights by plugging them in.

If the lights still don’t work, you can use the tool’s detector according to the manufacturer’s instructions to locate the problem area, then replace the bulb here.

What causes a section of Christmas lights to go out?

‘There are many components that make up a light set and therefore there are many factors that can lead to failure,’ explains John DeCosmo, president of Ulta-Lit Tree Company (opens in new tab) .

‘The more common light sets work in series fashion, meaning each bulb depends on the rest. If one bulb goes out, the entire section becomes unlit. That doesn’t mean the entire section is bad or needs new bulbs, but it means you’ll need to find that one to get the rest illuminated.

‘Old LEDs often had corrosion issues due to weather elements building up within the socket and keeping the bulbs from making a proper connection. Alternatively, squirrels for some reason love the insulation on light set wires and often chew on them, causing a break in the circuit and a nonfunctional light set.

‘A consumer might also plug too many incandescent sets end to end blowing a fuse in the first set but giving the appearance that all of the following sets also don’t work because they won’t illuminate.’

How do you know which bulb is out on Christmas lights?

You might be able to see which bulb is out on Christmas lights simply by looking. ‘You can identify which bulb on your string of traditional Christmas lights is out by looking for the bulb that is burned out or has lost its filament by looking at the tiny small filaments in the light bulbs,’ explains Imani Francies, home decor expert with USInsuranceAgents (opens in new tab) . ‘Frequently, the bulb will appear to be smoky as well.’

However, a bulb tester – or a tool that includes one of these, such as the LightKeeper Pro – is generally the simplest solution.

How can I fix Christmas lights without a tester?

A Christmas light tester is the preferred option but, if you don’t have a tester, it is still possible.

‘Start by visually inspecting the bulbs, making sure each bulb socket has one,’ says John DeCosmo. ‘There should be no missing or broken bulbs if you want to get this section to illuminate. Inspect the wires to make sure there are no breaks or exposed internal wiring.

‘Next, you’ll move on to testing bulb by bulb to ensure the bulbs are good. A functional section on that light set, assuming it has one, can be utilized as a bulb tester by simply removing one bulb and using that empty bulb socket to plug in a questionable bulb. If once entered, the bulb and the rest of that section illuminate then we have a good bulb.

‘While testing the bulbs, you’ll also want to visually inspect the sockets to ensure everything looks good in there and that there are no obstructions. If you have any issues, be sure to unplug the light set before attempting deeper analysis or repair.’

How to fix christmas lights

Lighting and trimming an indoor Christmas tree is one of the most treasured — as well as potentially troublesome — holiday traditions. If part of that tradition is the inevitable failure of a strand of lights, there are a few easy solutions you should try before you toss them into the trash.

Below, Eddie Bello, owner of Illuminations Holiday Lighting, and Gary McCoy, store manager for Lowe’s, walk us through how to troubleshoot Christmas light issues, so you can look forward to a bright holiday season.

1. Check the circuit breaker

When to try it: When none of the lights work.

If none of the bulbs in a string of Christmas lights work, and you also notice that other lights in the same section of the house go out, you’ve likely tripped the circuit breaker, says Bello. An overloaded electrical circuit — a situation where more electrical demand is placed on an outlet than it can handle — is the most common (and least serious) reason for this, he explains.

To check the circuit breaker, plug the lights into an electrical outlet. Next, reset the circuit breaker. To do this, locate the labeled circuit in the metal circuit box panel, which is usually found in your home’s utility room, basement, or garage.

Once you locate the circuit you believe is tripped in the panel, move the switch all the way to the “off” position, and then to the “on” position. You can often tell which circuit was tripped because the switch will be slightly out of alignment with the others.

If the bulbs light back up, an overloaded and tripped electrical circuit was likely your problem. This is good news, and you don’t need to do anything further, other than taking care not to plug in multiple high-voltage electrical items simultaneously in the same area of the house.

2. Replace the fuse

When to try it: When the entire string won’t light up

“If you have power coming from the outlet but your lights are not illuminating, it could be the result of a blown fuse,” says Bello. Replacement fuses are often included when you purchase lights, but you can also buy them at most stores carrying holiday lights, says Bello.

To replace the fuse, slide open the lid on the back of the plug that inserts into the outlet. If the fuse is blown, one of the fuse tubes will likely appear black in color or have visible burn marks, he says.

Take a small tool, such as an eyeglass screwdriver, and pry out the fuses. Then, gently press in the new fuses. Close the cover, plug the lights in, and they should work.

Bello notes that if the fuse blows again, it is likely due to damage in the light strand. If this happens, he says you should discard the lights and replace them.

3. Replace burnt-out bulbs

When to try it: When individual bulbs or parts of the string won’t light up

If the fuse isn’t the problem, there is probably a problem with a bulb, says McCoy. To fix burnt-out bulbs, untangle all string lights and check for frayed wires, damaged sockets, or broken bulbs.

Discard any damaged bulbs, and then replace them with spare ones. “Just be sure to use bulbs with the same voltage rating as the rest of your string lights,” says McCoy.

Quick tip: To increase the lifespan of a string of lights, replace burnt-out bulbs promptly. Leaving burnt-out bulbs on a string of working lights increases stress on the working lights, and shortens their lifespan, explains McCoy.

4. Test bulbs for damage

When to try it: When no bulbs are visibly damaged and the lights aren’t working

If no bulbs are visibly damaged, and your lights are not working, use a bulb tester, says McCoy. Follow the manufacturer’s instructions to test each bulb. Once you find the faulty bulb, unplug the associated light strand from the outlet and replace the faulty bulb with a new bulb. Be sure to firmly seat each bulb in its socket when replacing it.

Give lights a post-holiday check-up

A great way to prevent future problems is to test your lights at the end of the season, says McCoy. As you take down each strand of lights, replace any burnt-out or broken bulbs. Throw away strands with broken or frayed cords. When it’s time to trim the tree next year, your lights should all be working.

Quick tip: The best way to store Christmas lights to prevent damage is to “ball” them, says Bello. “To ball lights, hold the plug in your hand and wind the strand around your hand tightly to make a ball shape.”

Insider’s takeaway

Christmas light problems can quickly drain the joy out of your holiday decorating happiness. Tripped circuit breakers, blown fuses, and burnt-out bulbs are the most common problems, and thankfully, each one has a simple fix.

Before you pack your Christmas decorations away at the end of the season, give your string lights a post-holiday checkup. That way, you’ll look forward to a bright and trouble-free holiday next year.

Having trouble with your Christmas lights? Fix them with this guide!

Before attempting any part of this repair, make sure that the lights are completely unplugged from any electrical socket.

Common Issues:



3 Amp 125 Volt Christmas Light Fuses

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Шаг 1 Blown Fuses

Blown fuses are one of the biggest culprits of broken Christmas lights — especially if the entire chain of lights is non-functional. The good news is that they can easily be replaced!

With the plug in hand, slide the door marked "Open" in the direction pointed by the arrow.

Remove the two fuses, and inspect them by looking at them up against a bright background (such as the sky). If the fuse is good, you should see an unbroken strand of wire running between the two metal contacts.

Replace all blown fuses with new ones.

Шаг 2 Defective Light: Manual Instructions

If a specific section of the lights isn’t working, there might be a bad bulb, or a bad connection between the bulb and the socket.

Bulbs are generally made to not break the whole chain if the bulb burns out, but sometimes a manufacturing defect will prevent the bulbs from maintaining the electrical connection for the rest of the lights.

Gently grasp each bulb, and pull away from the socket. Inspect it and ensure that the two bulb copper leads are in their proper location, and not twisted or missing.

Continue with each non-functional bulb in the chain, up until you find the culprit(s). Replace the bulbs as necessary.

Шаг 3 Defective Light: Light Keeper instructions

You can also use a Light Keeper Pro or similar continuity testing device to pinpoint burnt out bulbs.

Plug in the strand of lights, and remove a bulb to connect the Light Keeper Pro to an empty socket.

Pull the trigger on the Light Keeper several times to bypass the bad bulb and light the whole strand, leaving the bad bulb dim.

Replace the bulb you used to test the strand, then remove and replace any bad bulbs. You can use the Light Keeper to test the new bulbs before you install them.

Шаг 4 Corroded Socket

Make sure the lights are completely unplugged from any electrical sockets before proceeding further.

Over time, the contacts inside the socket can become corroded or filled with dirt and grime. This can prevent proper contact between the bulb and the socket, which often results in no power to the bulb.

Use a small file or scratch brush to clean the wire contacts of the socket.

Once the socket is clean, insert a new bulb into the socket.

Шаг 5 Bad Socket or Wiring

Make sure the lights are completely unplugged from any electrical sockets before proceeding further.

If all else fails, the bulb socket may be broken beyond repair. Removing it is a cinch though, and should restore functionality to the rest of your lights!

Don’t do this for more than one or two sockets, cause it’ll raise the voltage on the rest of the strand and may cause other bulbs to burn out.

Use a wire cutter to remove the defective socket from the light strand.

Шаг 6

Strip about 1/2" of insulation from both wires.

Twist the wires together and insert them into the twist-on wire connector. Turn the connector several times until the cap feels secure, and you can tug on it without it falling off.

After testing the lights and making sure the bad socket fixed the problem, consider putting in some silicone sealant (or museum wax) into the cap in order to keep moisture out and prevent the wires from corroding.

To reassemble your device, follow these instructions in reverse order.

To reassemble your device, follow these instructions in reverse order.

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Geoff Wacker

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Good article, but like almost every other instructional topic on fixing busted Christmas Lights there are no instructions on how to actually get those little darn fuses replaced. What I mean is its easy enough to get the male electric cord plug compartment door open and the old fuses out, but getting the new Christmas light fuses to fit into the slots in many cords I’ve had is [email protected] near impossible. I have searched high and low throughout the internet and never found a video or article or any other webpage reference to issues getting the replacement fuses to properly seat into the fuse compartment slots. If someone could write about this subject and provide solid instruction on the best tools and methods to get those pesky little fuses to fit into the slots it would be a gem of a resource for those that do not want to throw strings of christmas lights away simply because the new fuses are so difficult to get to fit into the fuse slots in the electrical plug of the christmas light string.

I use paper clips to pry on one end and change them like batteries

My preferred tool is a small flathead screwdriver, such an eyeglass screwdriver. Use the flathead to push open the fuse panel in the plug, being mindful to hold the plug in a way that you won’t be injured if the screwdriver slips. That means holding the plug behind where you’re applying pressure with the screwdriver, and always pushing away from yourself rather than toward yourself. Holding the plug in a vise or with pliers also protects your hands.

Then pry up the fuse from the end, like you’re using a crowbar. Never apply pressure to the glass part of a fuse. To insert, push the fuse into the metal clips as far as you can by hand, then apply pressure with the flathead screwdriver to seat the fuse. ALWAYS push on the metal caps, and never push on the glass.

These are my preferred methods with everyday tools. If there are specialized tools for small light-strand fuses, a google search will yield info on those.

Agreed. If someone could help with this, I would be grateful. The rest of the task is a breeze, but removing the old fuses is hard and I am having no success getting the new ones in!

Mary/Shawn – this video explained it well for me:

If you have the right tool aka a micro-sized screwdriver with a flat head, it was easy.

Our Most Often Heard Christmas Light Troubleshooting Questions.

How to fix christmas lights

Why is half my light string flashing on and off?

There are a couple of reasons your Christmas light string is flashing .

How to fix christmas lights

Why are half of my Christmas lights out?

We hear this question from folks who are puzzled that their lights worked .

How to fix christmas lights

Why are my Christmas lights not working?

More than likely your lights are not working for one of the following .

How to fix christmas lights

How do I stop my LED lights from flickering?

Wonder why your LED lights seem to flicker or flash on and off in .

How to fix christmas lights

Can You String Too Many Christmas Lights Together?

Short Answer: Yes! The number of light strings that can be run in series .

How to fix christmas lights

Can I use your LED mini light bulbs to refill my .

We hear this question a few times a month and every so often when .

How to fix christmas lights

Can you shorten a string of Christmas lights?

If your light string is LED, they are ultra-low current and ANY kind of .

How to fix christmas lights

How many lights can be on one breaker?

Short Answer: For a 20-amp breaker don’t exceed 1900 watts if it is dedicated to .

How to fix christmas lights

Repairing Christmas Lights: Replace a C7 or C9 socket

One broken or missing socket on a C7 or C9 Christmas light cord can make .

Help from our Youtube Channel

How to fix christmas lights

Mini Lights – Changing a Fuse

How to fix christmas lights

Opening Fuse Door in a Christmas Light Plug

How to fix christmas lights

Replacing Lights on Christmas Yard Sculptures

How to fix christmas lights

Christmas Light Question: If one bulb goes out will the rest go out?

How to fix christmas lights

Changing a Christmas Light Bulb

How to fix christmas lights

Summary of our best troubleshooting tips

It happens. All of a sudden, half of your Christmas lights quit working. Your string of lights flashes intermittently. Or, worst of all, you plug in an entire run of light strings and they all light, then quit.

Here are some common things that cause these issues. It may just be 5 minutes and you’ll have your Christmas lights display up and fully functional again!!

My entire string of lights won’t come on. What do I do? (Or they flashed on and all went off.)

More than likely, you’ve blown a fuse. Check the specification of your light sets and see what the manufacturer says is the maximum connectivity. If you purchased your lights from us, there should be a maximum connection specification for your light sets.

If you exceed the maximum connectivity for your light strand it will blow the fuse.

Most sets of Christmas lights have fuses located in the male end-plug. Just use a short flat head screwdriver to slide back the door and replace the blown fuse with one of the two replacement fuses that originally came with your set.

If your light set comes on, then goes off when the set is moved, the plug prongs may need a little squeeze because they’ve either been stretched or you have an older plug.

Squeeze the plug prongs slightly towards each other to see if that solves an issue with your outlet or plug.

Half of my set is off. OR My set looks fine, it just doesn’t come on. How do I fix that? (And I checked my fuse already.)

More than likely, one of your mini light bulbs has popped out of its socket. Modern Christmas light strings are manufactured with a shunt wire that keeps the circuit intact if a bulb burns out. In other words, if a bulb burns out – the filament is blown – the rest of the lights stay lit. If a bulb becomes unseated or pops out of the socket, the electrical connection is interrupted.

Do a quick visual inspection of the side of the string that is out and make sure that each bulb is properly seated. A bulb can come loose in an installation or can be helped with little fingers. this is the number one reason light sets in reading nooks go out.

Whatever you do, don’t pull out and reinsert each bulb. That can create problems where there were none. (And wear off the skin on your fingers.)

If you’ve taken a look at all the possible causes for light strand outage that we’ve just reviewed and it doesn’t solve your problem, you may have an issue with the wiring – or your light set may be at the end of its lifespan and it’s time for it to retire.

Light strings that worked just fine before you took them down might have suffered damage during “de-installation” when they were taken down, wrapped and stored. Or they suffered in storage. High heat and pests can take a toll on lights.

(Friends from Wisconsin say that squirrels love to eat their lights.)

Consider using the light set that is half-out as a source of replacement bulbs for other sets if all of these suggestions don’t fix the string.

Issues with Rope Lights

My rope light has a section that has gone out. How do I fix that?

The rope light internal electric connections “float” to allow for twisting and bending the rope lights.

If they are twisted around too small of a diameter column or structure, the internal connections of the rope lights in the tightly wound area of rope may be disconnected.

Straighten out the section that’s unlit. That might be enough to repair the outage. If the unlit section refuses to light up, the next step for repair is to to cut between the cut-marks on each side of the outage and use invisible splice connectors to repair that part of the run.

My entire rope light went out, what do I do?

More than likely, the fuse is blown. Especially if the spool is incandescent and the entire length of rope is plugged in without unwrapping it from the spool. The tightly wound spool will instantly heat up, dropping the resistance of the rope lights and which overloads the fuses.

Replace the fuse in the plug housing. Hopefully, that will solve the problem.

How to fix christmas lights

Larry Campbell is an electrical contractor with 36 years of experience in residential and light commercial electrical wiring. He worked as an electronic technician and later an engineer for the IBM Corp. is a member of The Spruce Home Improvement Review Board.

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The Spruce / Nanor Zinzalian

  • Working Time: 15 – 30 mins
  • Total Time: 15 – 30 mins
  • Skill Level: Beginner
  • Estimated Cost: $10 to $20

The annual tradition of unboxing the Christmas lights always seems to be joined by the tradition of throwing away some of them. Plugging in a string of lights and discovering failed bulbs is all too common. So, the lights end up in the trash.

But it doesn't have to be like that. Holiday and Christmas lights are simple devices that should last you for many seasons.

With a few simple tools and inexpensive parts, you'll get your Christmas lights working again and your house will glow with cheer.

What You’ll Need

Equipment / Tools

  • Electric voltage tester
  • Christmas bulb tester
  • Christmas lightbulb shunt fixer tool
  • Flat-head screwdriver
  • GFCI tester (optional)


  • Replacement cartridge fuses
  • Replacement light bulbs


How to fix christmas lights

The Spruce / Nanor Zinzalian

Verify Power Runs to Outlet

All Christmas lights plug into a wall outlet for power. If no power is running to that outlet—or if the power is there but not getting to the lights—then the lights will not work.

Locate your home’s electric service panel. This is a box with a metal door and it is typically located in garages, basements, mudrooms, or in other areas that are out of the way but not hidden.

Locate the circuit that should be sending power to the outlet. Gently rock the circuit breaker switch toward the center of the panel. If the switch feels springy, it has been flipped off and no power is running to the outlet.

Rock the switch backward (toward the outer edge of the box), then back again toward the center. The switch should engage and send power to the outlet again.

How to fix christmas lights

The Spruce / Nanor Zinzalian

Verify Outlet Has Power

Go to the outlet again. Even if power is running to the outlet, the outlet may not be delivering power to the Christmas lights.

  1. Slide the light string plug in and out of the outlet. If it moves easily, the outlet may be old and the inner copper contacts are not touching the outlet’s prongs. Replace the outlet.
  2. Is the plug extremely tight? If so, this may be a tamper-resistant outlet. This is identified with “TR” on its housing. These outlets often grab the outlet too hard, making contact difficult. Push the outlet the rest of the way in.
  3. Is the outlet a GFCI outlet (identified by two buttons on the face)? Reset the button. You can test to make sure that your GFCI outlet is working correctly with an inexpensive GFCI tester.

How to fix christmas lights

The Spruce / Nanor Zinzalian

Check Christmas Light Fuse

One benefit of owning up-to-date Christmas lights is that they often come with an additional safety device: an on-board fuse. First, unplug the lights.

You'll find the fuse (or two) located in the cord's plug. With the flat-head screwdriver, slide open the door. Remove the tiny, cylindrical fuse.

Hold the fuse up to the light. If it is brown or black inside or if the filament is visibly severed, the fuse likely no longer works.

Insert a replacement fuse and plug the lights in again.

The small plastic bag of replacement lightbulbs that is often attached to the light string sometimes contains replacement fuses.

How to fix christmas lights

The Spruce / Nanor Zinzalian

Check and Re-Seat Bulbs

Individual bulbs in the string may be loose or they may be burned out. One way to check for this is to start at one end of the string and methodically go from bulb to bulb, pressing each bulb in and looking for obviously burned-out bulbs.

A more effective, less time-consuming way to essentially do the same thing is to use a Christmas bulb tester. First, make sure that the tester itself is working. Then, with the lights plugged in, turn on the tester and slowly pass it across the entire run of lights.

The tester will emit a constant sound and sometimes a light as long as it detects voltage. Once the tester reaches an area with no power, the beeping will stop.

Pull the bulb straight out. Do not twist. Push the fresh bulb straight in.

How to fix christmas lights

The Spruce / Nanor Zinzalian

Fix Lightbulb Shunt

Broken filaments aren't the only cause of bulb failure. Each bulb contains a secondary element that acts as a backup to the filament: the shunt. The shunt is designed to keep the electricity flowing, even if the filament is broken.

When the shunt fails to work, the entire string of Christmas lights fails.

There are a few tools that can repair failed bulb shunts, including one is called the Lightkeeper Pro. By squeezing the trigger of this device, you can repair bulb shunts. The Lightkeeper Pro can detect voltage within the line.

The Lightkeeper Pro can only repair shunts on incandescent Christmas bulbs. It does not work for LED Christmas lights.

How to fix christmas lights

Wondering how to fix Christmas lights? Whether you’ve already put your decorations up, or are planning to in the next few weeks, dealing with broken festive lights is a common issue at this time of year—especially if you reuse yours year after year. But below, we’ve shared how to quickly fix some of the most common lighting problems, so your home will be aglow before you know it.

When it comes to the most popular Christmas tree decorating ideas, warm white lights or colorful LED lights are some of the most popular options—a tree isn’t a tree during the holidays without them.

But whether you have one of the best artificial Christmas trees, or a real one, it’s often all too common to find when pulling them out of storage that, as soon as you are ready to decorate, either a fuse has blown, one or two of the bulbs has cracked or broken, or the wires have been (seemingly) irreparably tangled. Learn how to fix Christmas lights yourself with our guide below—be they hanging outside, on your tree, or on your mantel—so that your home can look as impressive as possible this festive season.

How to fix Christmas lights—four causes and how to solve them

1. Disconnected/loose light bulbs

Fairy lights are one of the most important pieces when planning your Christmas decorating ideas. But disconnect lights are guaranteed to put a dampener on things. If yours appear to be disconnected, the first thing to look out for is any loose light bulbs on your string of Christmas lights. If they are, solving the problem could be as simple as the light not being pushed into the power source properly.

Thomas Goodman, a construction and lighting expert at MyJobQuote said, “A tedious task (but a money0saving one), if your Christmas lights seem to be disconnected, ensure that each bulb is fully in its socket.

“Just one loose connection can break the whole circuit. Lights that hold 50 bulbs commonly work on 2 circuits, meaning that one loose bulb will break that circuit. If only half of your lights are working, this indicates a loose bulb.”

Check for loose connections and if you can see any, try and push them down onto the power connection properly to see if that fixes the problem.

2. Blown and tired fuses

Next check your fuse. Inside your lights there will live one or multiple small fuses and if one overheats and blows, it can cause one section or even the whole string of lights to stop working.

Goodman explained, “You may be able to recognize a blown fuse by sight alone. If the metal filament inside the glass cylinder of the plug has a break, this is a blown fuse. A break appears as a visible gap within the wire or as a dark smear within the fuse itself.”

You may have been provided with an extra fuse on buying your lights, but if you weren’t (or they’ve ended up rolling around somewhere in the random stuff drawer in the kitchen) you should be able to get one from a hardware store. You can even purchase them online if you know which type you’re looking for. But they are simple to replace.

How to replace the fuse:

  • Open the plug’s latch with a small screwdriver (any that you’ve collected from last year’s luxury Christmas crackers would work perfectly!)
  • Use a fuse tester to figure out which is the one causing the problem
  • Carefully take out the faulty fuse and replace it with the new one
  • Screw the latch back onto the plug and you should be good to go!

3. Broken lightbulbs

If all of your lightbulbs are connected properly and the fuses are all working/have been replaced for new ones, then chances are the issue could be that your lightbulbs themselves are broken.

When it comes to how to fix Christmas lights in this instance, you may think this means you need to splash out on a whole new set of lights. But it’s not necessary—you can just replace a single bulb. Replacement bulbs are actually super easy to get hold of—again, either from your local hardware store or online. If you’re not sure which type of bulb you need, bring your lights with you and ask an expert in the store.

The best way to go around this fix is to first check which bulb it is that’s causing the problem, as just one can cause a large section to go dark. Use an electrical tester to identify which bulb is the broken one. Then simply pick out your broken bulb and clip in the new one.

4. Chewed or mangled wires

Most of us can probably admit to storing our Christmas decorations in tattered old boxes that we keep in our cold attics or garages, or even outdoor sheds. And even the best Christmas decorations can be subject to wear and tear over time. So chances are that are precious Christmas lights are actually left subject to whichever animals want to get them.

This can lead to finding chewed wires when you open up your Christmas decor box, which, in all honesty, can be quite dangerous. Goodman explained, “45% of Christmas tree fires are caused by chewed wires. If wires are exposed, do not wrap them in electrical tape, instead, dispose of them correctly.”

In this case, it’s probably better to abandon ship and invest in some new lights—save any Home Alone-style electric situations!

While fixing your Christmas lights yourself is generally safe, Goodman warns that you should absolutely avoid and exposed wires, and leave it to the professionals in that case.

He told w&h, “Changing a fuse is certainly safe. Any exposed wires, you must leave them alone. A single bulb is 7.5 watts, this can cause a lot of damage if misused.”

And of course, if you simply don’t feel comfortable, calling in a professional is absolutely fine, although you’ll obviously need to be willing to part with your money for them to fix the issue.

To try and help avoid any damage to your Christmas lights this year, installing a Christmas tree skirt around the base of your tree can be helpful, as it will prevent curious hands and paws (from little ones and pets) touching power boxes.

With thanks to Thomas Goodman, a construction expert at MyJobQuote (opens in new tab) for his time and expertise for this article.

Aleesha is digital shopping writer at woman&home—so whether you’re looking for beauty, fashion, health or home buys, she knows what to spend your money on. She earned an MA in Magazine Journalism from City, University of London in 2017 and has since worked with a number of brands including, Women’s Health, Stylist and Goodto. A year on the w&h news team gained her invaluable insight into where to get the best lifestyle releases first—as well as an AOP awards nomination.

She’s in the know about the latest fashions, clever gadgets and reliable lifestyle buys—and being a product specialist on a brand for bold women means that Aleesha also knows a thing or two about the must-buy sex toys. When she’s not playing around with new products and testing anything she can get her hands on, Aleesha spends most of her time with her head in a current bestseller, trying out new recipes, exploring different wines and (in non-COVID times) has been known to be a bit of a jetsetter after spending a year living in Madrid.

Follow her latest shopping & lifestyle advice, beauty insights and social antics on Instagram at @aleeshabadkar (opens in new tab) . Your guide to reducing, reusing and recycling in San Luis Obispo County.

How to fix christmas lights

It’s the moment of truth every Christmas tree decorator has to face each year: When you unpack your Christmas lights, will they turn on?

If half your string of Christmas lights won’t light up, or worse yet — the entire string — don’t worry. Repairing Christmas lights is actually super easy! Watch these videos to find out how, no matter what type of lights you’re working with.

Remember: Always unplug your string lights before you start working on them! And if your string lights aren’t salvageable, here’s how to get rid of them.

How to Replace a Fuse on Any String Light (And Avoid Blowing More Fuses)

If your entire set of lights won’t turn on, or the string turns on briefly before going out, it’s likely you’ve blown a fuse. This is a super easy fix!

How to Repair Incandescent String Lights

A simple non-contact voltage tester will help you quickly find a bad bulb.

How to Repair LED String Lights With Removable Bulbs (No Fancy Tools Required)

If individual bulbs on your LED string are removable, you can use a pair of pliers to check the bulbs by hand. Because LED string lights have a different type of wiring, a regular voltage tester won’t work on them, but it doesn’t matter — broken bulbs are easy to identify when once you’ve pulled them out.

How to Repair LED String Lights With Permanent Bulbs (And a Faster Method for LED Strings With Removable Bulbs)

If you want a tool to quickly find where the current is failing, the only option currently on the market is a tool called the LED Keeper. The LED Keeper is a good tool for you if:

  • You have a lot of LED string lights to repair;
  • Your LED string lights have 100+ lights in them; or
  • The bulbs in your LED string lights are not removable.

The LED Keeper gives you a way to find and bypass any broken bulbs in your LED string.

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Troubleshooting & repair tips for fixing broken Christmas lights.

How to fix christmas lights

This article focuses on basic troubleshooting for Christmas mini lights and hardwired string lights that cannot be cut. To learn how to cut and customize SPT1 & SPT2 light strings visit our custom Christmas lights guide.

Click on a topic below to be taken straight to that section:

Items you might need:

  • Light Tester
  • Replacement Bulbs
  • Spare Fuses

Problem: Entire String Not Working

Possible Cause: Fuse burnt out in plug
Suggested Fix: Replace the plug fuse

Possible Cause: Loose or broken bulb
Suggested Fix: Use a light tester to identify and replace loose or burnt out bulbs. If you don’t have a light tester, you can check each bulb on the string for tightness and look for visual clues, like cloudy or dark glass, to identify bulbs that need to be replaced.

How to fix christmas lights

How to fix christmas lights

Problem: Half of String Not Working

LED Strings with Rectifiers: Some LED Christmas lights are designed with one or more rectifiers placed along the string to help prevent bulb flickering. If part of the string is out, it is possible that there’s an issue with the rectifier and the entire string will need to be replaced.

How to fix christmas lights

Problem: Random bulbs not working

If the light string has removable bulbs, replace any bulbs that aren’t working. Most incandescent mini light strings include replacement bulbs. If you need more replacement mini bulbs, they can be found online and in some home improvement stores. If the bulbs can’t be removed and replaced, the entire string will need to be replaced.

Problem: Lights flickering when string is moved

If bulbs are flickering when the light string is moved, this is likely caused by damage to the wiring and the light string will need to be replaced. Additionally, if you notice cracked insulation, a damaged plug, or frayed wires anywhere on your Christmas lights, we recommend replacing the entire set even if it is currently working.

Problem: Lights dimming when plugged end-to-end

Possible Cause: If you’re plugging multiple Christmas light strings or lit decor items together end to end or with stackable plugs and some are dimming or won’t turn on, it’s possible that you’ve exceeded the max capacity of your outlet or light strings. All string lights and lit decor items have a maximum wattage capacity for end-to-end connections, and when you reach that limit you risk blowing plug fuses, tripping breakers in your fuse box, or creating a dimming effect in your lights.

Suggested Fix: If you run into any of these issues while plugging multiple lights together, check the fuses in any strings that won’t light and replace them as needed. After changing any blown fuses, determine the max wattage capacity of the strings or lit decor you are using and reconfigure your end-to-end connections as needed. You may also need to reroute extension cords, so that part of your display plugs into a different outlet on a different circuit.

To learn more about max capacity for string lights, visit our Christmas Lights Wattage Guide.

It’s a Christmas miracle! Restore your lights and save money with these helpful tips.

It’s happened to all of us. We’ve spent hours during the holiday season perfectly planning and hanging holiday lights on our Christmas tree. Suddenly, we find ourselves experiencing a Clark Griswold moment, and we spend additional hours searching for the source of the burned-out Christmas lights. Rather than giving up and driving to the store to buy a whole set of new ones, here’s how to fix Christmas lights once and for all. It’s easier and more affordable than you might think!

Find the Source of the Power Outage

These days, most holiday mini lights aren’t meant to last forever. They’re only designed to make it through about three seasons tops (about 1,000 to 1,500 hours). But if you find your Christmas lights conking out on you earlier than that, there’s likely an easy fix. When you discover a broken strand of lights, try to determine what’s causing the lack of juice. Here are the most common causes.

Chewed Wires

Bad news: Squirrels and mice are strangely attracted to something in the wire, and they will go to town on them if they have the chance. If you see frayed or chewed wires of any kind, you should throw them away immediately. We can all agree that it’s better to buy a new strand than get electrocuted by rogue wires, right?

Blown Fuses

Behind a small door in the male end of your strand’s socket are a number of small silver fuses. These can get overheated and stop working. Whenever you purchase a box of lights, they generally come with a small packet of replacement bulbs and an extra fuse or two. Use a small screwdriver to open the small latch and be careful to not let them fall out when you do. There are electrical tools as well as fuse testers out there that you can purchase to test which specific fuse is the problem.

How to fix christmas lights

Light Bulb Connection

Sometimes a fix is as easy as looking to see if any of the light bulbs on your ailing strand aren’t pushed down into the connector enough. If the fine wires on the end of a light bulb aren’t able to connect to the power source, a loose connection is probably your culprit.

How to fix christmas lights

Broken Bulbs

If all is well with your fuses and all the lights are pressed securely in their spots, it’s time to assume that the problem lies with one or more of your light bulbs. Luckily, replacement bulbs are easy to come by and cheap! You can also keep a “sacrificial strand” on hand—any time you need extra bulbs, you can pull them from this strand that’s around solely for use as replacements.

It’s the Bulb…But Which One?

You’ve determined that the problem is a bulb. Sometimes you can actually see the very bulb that has stopped working, but on most sets of lights, if one bulb is out, they’re all out. Because the strands work on a circular electrical system where electricity flows through all the light bulbs and then returns to the power source, it’s often one bulb (or sometimes several) that ruin things for all of them.