Why Won’t My LED Lights Work After I Cut them?

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Most probably, you are looking for an answer to the question, “Why Won’t My LED Lights Work After I Cut Them?” If that’s so, then you are in the right place.

There are places where you can only cut LED tape. These places are called “Cut Marks.” They usually have dotted lines across the tape, and they often have visible copper busses at the cut marks so that they can be reconnected.

Why Won't My LED Lights Work After I Cut them
Why Won’t My LED Lights Work After I Cut them?

If you cut somewhere else, you may not use tape. At the very least, if you cut the tape in the wrong place, it won’t work anymore. At the very worst, the whole tape won’t work anymore.

This article will share the reason for the not-working LED lights after cutting them with the easy cutting guide! Keep reading till the end of this article to get the answer to “Why Won’t My LED Lights Work After I Cut them”?

Why Won’t My LED Lights Work After I Cut them?

If you want to light up your kitchen cabinets or backlight your TV with LED strip lights, there’s a way to do it. LED strips are popular because they can be used in various ways. They are made up of a series of LED emitters on a small, flexible circuit board.

People should worry about only one thing. Most LED strips come on long reels between 3 feet and 16 feet long. No, they won’t.

Yes, LED strip lights will work after they’ve been cut as long as you cut along the lines. Cut lines show where one circuit ends and the next one starts. Each LED strip is made from several circuits, so each cut line shows where one circuit ends and the next one starts.

If I may say so briefly, the LED light bar is a circuit made up of three LEDs connected in a series-parallel way. Each of the three LEDs can be cut, the length can be cut off, and the short can be soldered. So it’s possible that you cut the wires short, which would make the LED light bar not work.

That’s why the LED strip will stop working if you cut it somewhere else. This could prevent the whole strip from working.

Can you cut LED light strips?

LED Strip Lights are the most versatile types of lighting options out there, and this isn’t just because they are flexible. They can be used in many different ways, and this isn’t just because they can be moved.

If you want them to fit in with your project, no matter how big or small it is, you can cut them to the lengths you need. Because the process is so easy, you can do it on your own. Suppose, for example, that your strip lights are a little too long for the space where you want to put them.

You can cut off part of the end to make it fit. If you have a long, single strip of LEDs but want two separate pieces, you can cut the strip in half.

If you buy LED Strip Lights, you can cut them at 5 or 10 cm intervals, depending on the type of strip light you buy. Lines show where the “cutting points” are.

To cut your strip lights apart, cut along the line with a pair of scissors or a craft knife. Keep your tool sharp at all times because a blunt instrument could damage the circuit board and other parts.

LED Strip Lights are made in a way that makes them work even after they are cut. This is because their circuit is completely shut off at each point where they cut something. If you want to cut a section off the end of your strip light, make sure you cut it away from the connector at the end.

To cut your strip lights into two parts, you will also need to solder some parts together. Cutting points should have solder points (circular metal discs). There should be two solder points in the case of single-color lights, and four solder points in the case of color-changing RGB LED lights.

If you want to connect a new piece of 2 or 4 core cable, you’ll need to solder the wires to their correct solder points (which should be marked for this purpose).

Soldering isn’t hard, but you need the right tools, which most people don’t have. Asking an electrician to do the soldering for you will also cost a lot because you have to pay for their time. The cheapest and safest thing to do is ask your retailer to do everything for you.

What happens if you cut your LED strip lights in the wrong place?

How to Cut a Strip Light in a Safe Way?

LED strip lights are made to be easily separated with a pair of scissors. At the end of each LED is a pair of copper dots. All LEDs will work as long as you cut between the dots. The LEDs can then be connected to a power source through a fast connector or soldering. All LEDs should light up in a colorful display if they are appropriately connected.

We have separated the cutting process into three parts for you. Please follow every part one by one as we mentioned below for the right process of cutting LED strip lights!

Part: One

Why Won't My LED Lights Work After I Cut them
1st (Photo Credit: WikiHow)

1st- Determine the length of LEDs required. The LEDs are packaged in a single continuous strip. Individual LEDs can be cut off as needed, but they must be cut at specific points to function correctly. Determine the length of your LED strip before turning off any lights.

Why Won't My LED Lights Work After I Cut them
2nd (Photo Credit: WikiHow)

2nd- Locate the cut line on the copper dots of the LED. On the back of the LED strip, look for a pair of copper dots. The copper dots indicate where each light on the strip connects to the next one. A dotted cut line will run between the copper spots. Select the line closest to the LED length you measured previously.

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3rd- Using scissors, cut the LED strip apart. A pair of scissors will suffice. Hold down the lights and cut along the dotted line. You should be severing the copper dots. To avoid injuring the LEDs, precisely align the cut.


Part: Two

1st (Photo Credit: WikiHow)

1st- Line up the fast connector and the LED strip. Quick connectors, which can be purchased alongside LED lights, are convenient to complete the electrical connection. A + and – will be printed on the back of the LED. Connect the connector’s black wire to the – and the red wire.

2nd (Photo Credit: WikiHow)

2nd- Remove the 18-inch (0.32-cm) plastic bar from the quick connector. With one hand, hold the connector. Find the little plastic bar at the end, which is generally black. To open the connector, pull this bar forward. Take caution because the connector is sensitive.

Why Won't My LED Lights Work After I Cut them
3rd (Photo Credit: WikiHow)

3rd- Remove the LED’s adhesive backing 14 in (0.64 cm). Remove the LED’s backing just enough to reveal the copper terminals at the end. If your LEDs do not have this backing, you must clip the plastic off the connections.

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4th- Connect the LED to the connector. Insert the LED’s end into the fast connection. Check that the wires are correctly aligned. The black wire should be connected to the + and the red wire to the -.

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5th- Snap the fast connector’s plastic bar shut. Pull the plastic bar back onto the LED to secure it. When you let go of the LED, it should not move. This also guards against harm to the connection.

Why Won't My LED Lights Work After I Cut them
6th (Photo Credit: WikiHow)

6th- Connect the fast connector’s wires to the power source’s same-color wires. Use a terminal wire connector from a hardware store. Plug the wires into the connector, then tighten the connector screws clockwise to secure the cables. Connect the power supply cord to the other end of the terminal.


Part: Three

Why Won't My LED Lights Work After I Cut them
1st (Photo Credit: WikiHow)

1st- Remove the plastic cover from the LED strip’s end. Make use of a sharp knife or a box cutter. Cut the plastic just above the copper dots at the LED’s end. Scrape the blade along the copper dots to remove away any plastic debris after removing enough plastic to expose them.

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2nd- Place the metal on top of the copper terminals and solder it in place. Warm-up a soldering iron and place a piece of metal solder wire over the LED. Directly melt the solder wire onto the copper spots. Use just enough solder to create little puddles of metal that thoroughly cover the copper.

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3rd- Make a small hole in the end cap of a plastic bottle. Purchase a plastic end cap at a home improvement store. Pierce the closed end of the cap using a knife or box cutter. Scrape away at the plastic till the opening is wide enough for wires to pass through.

Why Won't My LED Lights Work After I Cut them
4th (Photo Credit: WikiHow)

4th- Trim the wires to size and thread them through the cap. You’ll need a black and red wire to connect to the LED’s terminals. Determine the length of wire required to connect the LED to the power source. Leave about 12 in (1.3 cm) of additional length on the end of each wire.

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5th- Use wire strippers to remove the wires. Remove roughly 12 in (1.3 cm) casing from the wire ends. Clamp the wire strippers to the end of the wire. To cut through the wire casing, press down on the handles.

Why Won't My LED Lights Work After I Cut them
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6th- Twist each wire end and solder it. Work on only one wire at a time. Twist the wire’s end to bring all of the ragged strands together. Melt the solder onto the exposed wire after reheating the soldering iron. Repeat for each wire.

Why Won't My LED Lights Work After I Cut them
7th (Photo Credit: WikiHow)

7th- Connect the wires to the LED with solder. Match the polarity, with the black wire aligned with the – of the LED and the red wire aligned with the +. Touch the solder on the LED with the soldering iron to liquefy it before attaching the cables. Hold the wires in place until the solder has resolidified.

Why Won't My LED Lights Work After I Cut them
8th (Photo Credit: WikiHow)

8th- Connect the cables to the power supply. Connect the other end of the wires to the power supply. Before testing the electrical circuit, you may need to twist the wire ends and cover them with a shrink tube or an end cap.

Why Won't My LED Lights Work After I Cut them
9th (Photo Credit: WikiHow)

9th- Attach the LED with a silicone end cap. Obtain a new plastic end cap. Halfway fill it with silicone glue. Then, slide the cap onto the LED strip’s free end. Ensure that the LED reaches the back of the cap.

Why Won't My LED Lights Work After I Cut them
10th (Photo Credit: WikiHow)

10th- Put the LED lights to the test. Toggle the power source on and off. All of the LED lights should turn on. If they don’t, the cables may not be properly installed. Check that the colored wires are connected to the relevant LED terminal. Additionally, ensure that the wires are securely soldered to the LED.

Check the video for more understanding…

Troubleshooting: LED Strip Not Functioning After Cutting

While customizing the length of your LED strips may appear to be simple, mistakes sometimes arise.

Check if your LEDs were designed to be cut if they aren’t working after being cut.

If they weren’t, but you cut them anyway, then the damage has already been done. Because the circuit in these lights runs continuously over its whole length, cutting it would have irreversible harm.

If your strip was meant to be cut, the next step is to make sure you cut in the right place.

Cut outside of the cutting line, and that circuit will be killed. You’ll have to cut back to the closest cutting line, which will kill that circuit.

There are a few other issues to be aware of, but they are not directly related to the cut but rather how the strips are connected.

You’re experiencing a voltage drop if your LED strip setup works but is a different shade of brightness at each end.

In general, 12V LED strips should not be longer than 10 feet, and 24V LED strips should not be 15 feet. Voltage dips can be avoided by lowering the length of the strip per power supply.

If your RGB LED strips aren’t changing color, it’s possible that you misconnected them, and the polarities were reversed. Flip your strip around and reconnect it to fix the problem.

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