None of them would have worked. Sometimes, if I drop it or jar it a bit, the entire thing lights up and will carry a current to the next set of lights. See "LED Christmas Lights and How to Fix Them" by Terry Ritter. Sadly, I cannot reproduce that effect. Yes, the LED Keeper can find the culprit. Why are there two fuses in Christmas lights? Why does only half of mini Christmas lights string work? Tighten the bulb gently and checked to see if the rest of the strand lit up. 100 bulbs is a popular configuration. Like the incandescent strings before them, the, Pull out one bulb at a time, and stick a piece of folded up foil into the bulb socket. Then, how can you tell if a Christmas light fuse is blown? A regular strand of incandescent lights work, but whenever I plug in a strand of led lights in, only half of the strand works. Why did the eastern half of the Roman Empire last longer than the western half of the Roman Empire? Click to see full answer Also asked, why do only half of my LED Christmas lights work? How much does it cost to play a round of golf at Augusta National? When it comes to lens damage, the general rule is if the lens is cracked all the way through to the core of the LED, then either the entire set or on longer stringers, half the set will go completely out. Once you’ve installed them, you can paint them to match the ceiling and leave them in full time. Why is it that if you pull out or break one of the bulbs, the whole strand of lights goes out? High heat and pests can take a toll on lights. This begs the question why bother providing the fuse. Sometimes, if I drop it or jar it a bit, the entire thing lights up and will carry a current to the next set of lights. Your lights may turn on for a few seconds before you hear a popping noise and the lights cut off again. BTW the above instructions apply to the common configuration of having every other bulb belonging to a given string. Stuff like that spells FIRE! Why is it always half-way down the string. Holiday lights usually have cartridge fuses in a small compartment in the cord plug behind a sliding door. Just like finding an LED that is open except not looking for the LED's to turn on, but will increase slightly in brightness. So, you’ll have three wires–one common, one for one string and one for the other. Noma does not give appropriate directions on the maintenance of their string lights. The flasher bulb will only cause the circuit it is a part of to flash on and off. Or they suffered in storage. If one bulb dies, it can cause the rest of the strand to stop working. Does anyone know why half a string of Christmas lights light up and half do not? Does anyone have a good idea of how to fix these lights? this is the cheapest construction method dating way back from incandescent light strings. Don't force them in. We couldn’t fix it by replacing the bulb right where the light string stopped working, so I looked into it and found this helpful (but a little too technical) article . If the string is still dark, continue to the next step. In Canada at least, the three wire system is generally one that is equipped with a plug at one end to attach to the wall outlet, and an outlet at the other end to attach a second string of Christmas lights. Don't pitch 'em, you can FIX them, and it's pretty simple, … Step 1 Blown Fuses With the plug in hand, slide the door marked "Open" in the direction pointed by the arrow. If the fuse isn't the problem, there's a problem with a bulb. If one bulb dies, it can cause the rest of the strand to stop working. So I went to Walmart because someone told me they had cheap lights. But, just a fickle as the first rough handling, a subsequent rough handling causes the lights to go off again. Unplug the lights. Close the plug door. I've checked for missing bulbs, and these days the string is supposed to stay lit when individual bulbs burn out. It’s not as bad as it sounds from my description. Powered by Discourse, best viewed with JavaScript enabled. Plug the string of lights into a normal outlet. If you discover that the bulb is burned out or damaged, replace it with a new bulb, but be sure it has the proper voltage rating or you risk damaging the whole light set. Unfortunately, if any bulb is loose or burned out, it will disconnect all the bulbs in that string. I plug my lights in and I have a bunch that just don’t turn on. If the pattern is different, you’ll need to modify the testing procedure as necessary. I have 8 strings but with 4, only 1/2 of the lights work.