Christmas Lights Worked Last Year, Dead This Year: Why
Strings that were working perfectly when they came down are dead or partly dead coming back out.
The short answer
Nothing failed while the box sat still - the damage happened during takedown, during storage, or from heat. Check three things in order: the fuse in the plug, whether any bulbs have worked loose, and whether sockets are cracked or crushed from being packed under weight. In Georgia specifically, an attic above 120 degrees for months does real damage to PVC insulation, so where the box lived matters as much as how it was packed.
What is actually causing it
In the order we find them, most common first.
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1.A blown fuse in the plug
most commonHow to check: Slide open the cover on the flat face of the plug and hold the glass fuses to the light. A break in the filament or blackened glass means it has gone.
The fix: Fit a matching 3A replacement. It may well have blown last January as you unplugged everything, and you simply had no reason to notice until now.
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2.Bulbs worked loose in the box
Free to fix most commonHow to check: Press every bulb firmly into its socket, especially across any dark section.
The fix: Seat them. Months of being moved, stacked and jostled backs bulbs out of their sockets, and it costs nothing to rule out first.
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3.Sockets crushed under the weight of the bin
Free to fix commonHow to check: Look for sockets that are cracked, oval rather than round, or have contacts flattened inside.
The fix: A cut-to-length C9 run can have the damaged span cut out and re-plugged. A moulded retail string with crushed sockets is finished - and this is the argument for reels over bins in one sentence.
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4.Attic heat degrading the insulation
commonHow to check: Flex a length of wire. If it feels stiff, chalky, or shows fine cracks as it bends, heat has aged it.
The fix: Retire it. Georgia attics run well above 120 degrees for months, and PVC that has cooked is brittle and no longer safely insulating. Store next year's somewhere cooler.
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5.Corrosion from being packed away damp
Free to fix commonHow to check: Pull a bulb and look inside for green or white powder on the contacts.
The fix: Light corrosion on one or two sockets can sometimes be cleaned. Widespread corrosion means the strings went into the box wet, which is the actual habit to change.
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6.Rodent damage
less commonHow to check: Look for chewed insulation and droppings in the box. Common in garages and attics, and easy to miss on a dark green wire.
The fix: Any chewed wire is scrap - do not energise it. Store in sealed containers rather than open bins or bags.
Bringing them back
- 1
Inspect before you plug anything in
Unroll each string and look along it for chewed, cracked or stiff wire and for crushed sockets. Finding damage before applying power is the whole point of this step.
- 2
Check the fuse
Open the plug and check both glass fuses. This is the most common single cause and the cheapest to put right.
- 3
Press the bulbs home
Work along the string seating every bulb, paying attention to any dark section. Bulbs back out of sockets constantly in storage.
- 4
Test each string on its own, indoors
Plug in one string at a time before anything goes up a ladder. Ten minutes at a bench beats finding a dead run once it is on the roof.
- 5
Retire anything stiff, chalky or chewed
Heat-aged and rodent-damaged wire does not get another season. This is the one point on this page where replacing is the correct answer.
- 6
Change how you store the survivors
Wind each run onto its own reel, label it with where it goes, keep the clips separately, and store somewhere other than the attic. This is what stops the whole list happening again.
Every November brings the same discovery: the box that went into the attic in January, working, comes out in November not working.
It feels like the lights failed in storage. They did not — nothing electrical fails from sitting still. What happened is that they were damaged on the way in, or by where they spent the summer.
The three-minute triage
Before writing anything off:
- The fuse. Open the plug and check both glass fuses. Fuses blow at odd moments, including as everything is unplugged in January, and there is no way to know until the following year.
- Loose bulbs. Months of being moved, stacked and shifted backs bulbs out of their sockets. Press every one home.
- Crushed sockets. Look for sockets that have gone oval, cracked, or have flattened contacts. This is what happens when a bin of lights has a box of decorations stacked on it for eleven months.
Between them, those three account for most of what looks like total failure.
The Georgia-specific one
This deserves its own mention because it is regional and it is frequently the real answer.
An attic in North Atlanta spends months of summer above 120 degrees. PVC insulation does not enjoy that. What it does is slowly stiffen and lose plasticiser, so wire that was flexible in January is brittle by November — and brittle wire cracks at the first hard bend over a gutter edge in the cold.
The test is simple: flex a length of it. Stiff, chalky, or showing fine cracks as it bends means heat has aged it, and it is finished regardless of whether it still lights on the bench.
Test on the bench, not the ladder
Every professional installer tests strings at ground level before anything goes up. Almost no homeowner does, and it is the biggest single difference between a smooth install day and a bad one.
Ten minutes with each string plugged in at waist height finds every fault on this page while they are still easy to reach.
The actual cure
All of this is preventable, and the prevention is unglamorous: one run per reel, wound not coiled, labelled with where it goes, clips removed and stored separately, and kept somewhere that does not bake.
That is the entire method, it costs about twenty dollars in reels, and it is why our own strings last many seasons. The storage guide goes through it properly — it is the least interesting page on this site and probably the one that saves the most money.
As an Amazon Associate, Christmas Lights North Atlanta earns from qualifying purchases. We list these because they fix the problem above — where the fix is free, we have said so.
Diagnose before you replace
Most strings that come out of a box dead are a blown fuse, a crushed socket or one failed bulb. All three are cheaper to fix than to replace.
allsun Christmas Light Tester and Fixer with 50 Bulbs & Battery Tester
A tester, fuse checker and non-contact voltage pen in one kit. The voltage pen is the part worth having anyway — knowing a cord is live before you handle it in the wet is basic safety.
$14.90
See it on Amazon
Light Keeper Pro-The Complete Tool For Fixing Your Christmas Lights
The classic tool for finding the one dead bulb taking out half a string. Cheaper than replacing the set, and it turns a thrown-away string into a working one in about a minute.
$24.90
See it on Amazon
smseace 3A Christmas Light Fuses 20Pack 3A 3AMP 125 Volt Fuse 0.14 x0.39…
The fuse that lives in the plug of most light strings, twenty for the price of a coffee. A blown fuse looks exactly like a dead string, and this is the first thing to check before you throw anything away.
$3.99
See it on AmazonThen store them so it does not happen again
This is the actual cure. Wound on reels and kept out of a Georgia attic, commercial strings last many seasons; balled in a bin they do not see a third.
Christmas Light Storage Bag
Four reels inside a 500-foot bag, so the reels and the thing you carry them in arrive together. The right size for a one-storey roofline plus a couple of shrubs.
$19.99
See it on Amazon
Christmas Light Storage Bag with Reels- Holds up to 750ft of Mini Lights.…
Rated to 750 feet of mini lights, which is a whole typical display in one bag. 600D fabric survives being dragged out of an attic annually.
$35.99
See it on AmazonPrices checked Jul 27, 2026 and may change.
Related questions
Why do Christmas lights stop working in storage?
They rarely fail while sitting still. What fails is caused by handling and environment: bulbs backing out of sockets while the box is moved, sockets crushed under whatever was stacked on top, fuses blown during takedown, moisture packed in with them causing corrosion, and heat aging the insulation. Every one of those is a storage-method problem rather than a product problem.
Can I store Christmas lights in the attic?
You can, and in Georgia it is the harshest option available. An attic here sits well above 120 degrees for months, and sustained heat makes PVC insulation brittle so it cracks the first time you bend it in December. A garage, basement or interior closet is meaningfully kinder. If the attic is genuinely the only space, use a sealed container and expect a shorter life.
How should I store Christmas lights so they work next year?
One run per reel, wound rather than coiled, labelled with where that run goes, with clips pulled off and stored separately, kept somewhere that does not bake. That combination prevents nearly everything on this page, and it turns next year's install into unrolling a labelled reel instead of an hour untangling on the garage floor.
Is it worth testing lights before putting them up?
Always, and at a bench rather than on a ladder. Ten minutes plugging in each string indoors will find every fault on this page while they are still at waist height. Every installer does this; almost no homeowner does, and it is the single biggest difference in how the day goes.
My lights look fine but the wire feels stiff. Is that a problem?
Yes. Stiff, chalky wire that shows fine cracks when flexed is heat-aged insulation, and it will crack properly at the first sharp bend over a gutter in the cold. It may light perfectly on the bench and still be at the end of its safe life. Retire it.
In the North Atlanta suburbs and would rather not deal with it?
We design, install and maintain displays across Alpharetta, Roswell, Johns Creek and the surrounding area — and if something fails mid-season on a display we installed, fixing it is included. Call (470) 888-0030.
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