How to fix led christmas lights ? Best steps in 2021.

Christmas lights are a real nuisance for repair. The hard part is finding the bulb that has burned and most people do so by trial and error. If you have a coil of LED lights that are of non-replaceable type, you may think that all is lost. But don’t be too hasty. What if you could detect the problem LED and then repair the string. Let me illuminate the solution in how to fix led christmas lights


You will need some equipment that most people have that is electrocuted.

WARNING(how to fix led christmas lights)

The following includes working with electricity. If you do not know what you are doing then lightning can kill you. So if you are not qualified to repair the equipment requiring electricity, do not attempt the following repair.

If you follow these instructions then you take full responsibility for being electrocuted – which may kill you as stated earlier – or for other risks associated with the activity outlined in this set of instructions.

For example, if you burn yourself with a soldering iron that is your fault. If you have lead poisoning by eating lead solder, then it is your fault. if you burn your house because you have not done your repairs properly then it is your fault. If your spouse shakes you with a rolling pin because you have destroyed his Christmas light, then guess what your fault is.

Equipment and necessary materials

The necessary equipment are:

Voltage detector (see picture for example)

soldering iron


heat shrink tube

Wire cutter

Wire strippers

Circuit explanation

how to fix led christmas lights

I am working with a 70 light string consisting of two parallel circuits with 35 lights in each series. The circuit breaks when one of the LEDs fails which affects all other lights (half of them) that are in the same series circuit. how to fix led christmas lights.

Another factor to consider is the current range of an LED. Many of the LEDs do not like current, so apart from the LED, each light also has a current lighter resistor. For this christmass light  repair we need to bypass the faulty light. This will increase the current that passes through the remaining lights as we have exhausted part of the resistance.

However, ejecting a light should not increase the current so as to damage the remaining LEDs in the same circuit. There is definitely a limit. Bypassing any excess, two lights in the same series circuit would potentially increase the current so that the remaining LED lights would be jeopardized which would surely destroy the entire half of the light string.

Search (detection)

The step 1 is to find out the faulty LED that is no longer working . The  LED which is not working will obviously be in string half that is not working.

Let the lights plugged in, with using a voltage detector to check the live voltage wire between each light, starting at the end that plugs into the wall light. The voltage must be detected on the live wire going to the first light.

Then check the wire going from the first light to the second light. Lets assume that the first half of the christmas light string is not working. If it is the second one then start at 36 lights for a 70 light string.

Keep checking the voltage between lights. As soon as you find a wire between the lights that is no longer a voltage, the light is detected before it is likely that the fault is the light. As an example, if there is a voltage on the wire between light 6 and light 7, but not the voltage between light 7 and light 8, then light 7 is the probability of the problem. how to fix led christmas lights.

Just to make sure to do a definitive test for the voltage between the next set of lights. Voltage should not be detected.

Verification – Ignore

I did this to prove a concept. It is not part of the instructions. You can get electrified.

When I was sure about the LED that was faulty, I unplugg the lights from the electrical source and then put a sewing pin through the wires going to the LED to bypass the light in question. how to fix led christmas lights.

After making sure that the pin was not touching something conductive, I plugg-ed the lights back in and the light string half that did not work before did not work except for the bypassed light with the pin. It proved that I got a defective LED.

I then unplugged the lights and started repairing.


At this point I cut the wires going to the faulty LED, put my heat shrink tube (2 tubes) on, plugged the wires in, and shrunk the tube.

Defective LED light with light string half remov which did not work now minus 1 light is working.

As I mentioned earlier, removing one light will increase the current and the LED does not like high current.

The measured current in the light string half that was not faulty and it was 9mA. The light string with a light was remov-ed by measuring the current in half 12mA. The normal upper limit of the LED is 20mA so the current level is still reasonable with the light remov.

I am happy to say that even after two weeks the lights are going well.

Can LED Christmas lights be repaired

After decorating, for hours you finally plug in your LED Christmas lights, and nothing happens.

You start thinking things like “You thought that These were to last forever,” and “Are these LED lights really worth it?” and “my money got wast-ed” how to fix led christmas lights.

They are, and they can be fixed.

Take a little time to think about the good side of LED lights before you give up on them and go back to incandescent Christmas lights again.

Here are some LED light reminders and tips to fix your broken Christmas lights.

Detect bad bulbs(how to fix led christmas lights)

how to fix led christmas lights

If one of your LED light strands is not working, it is probably just because it has a bad bulb. If one bulb dies, it may prevent the rest of the strand from functioning. The only way to fix the problem is to find a bad bulb.

Sometimes only a section of lights will go out, which will make your work much easier. how to fix led christmas lights.

You need to check the entire bulb wheather all are working or not.

This means pulling each bulb, replacing it with a good bulb, and plugging it in. If it turns on, you get a bad bulb. If it does not turn on, you must take out the replacement bulb, bring back the original bulb, and move on to the next bulb.

It is a slow process, but it is very easy to find the right bulb.

Before installing the leds test every strand of Christmas lights before you hang them on the roof or wrap them around the tree. It is much easier to fix them on the ground than suspended on a ladder.

So here is the end of how to fix led christmas lights? Hope you like the content. Thank you.

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