Guida ai problemi comuni e alle soluzioni per le luci a striscia LED

Available in a wide range of sizes, densities, and colors, LED strip lights have become a popular choice for homeowners and businesses looking to create ambiance or enhance their décor due to their ease of installation. However, like many lighting fixtures, LED strip lights can encounter issues that affect their performance. As a result, troubleshooting and fixing LED strip lights can be one of the biggest headaches.

But don’t worry! Through SignliteLED’s years of experience in developing, manufacturing, selling wholesale, and using LED light strips, we’ve summarized some of the most common causes of LED light strip failures as well as solutions you can take to fix them to help you learn how to diagnose and repair flickering or damaged light strips. In this guide, we’ve likely covered the specific problems you’re experiencing, with each problem briefly explained and a simple solution provided.

Safety Tips Before You Begin

Before diving into the troubleshooting process, make sure you prioritize safety, which always comes first. Although LED light strips are also low-voltage DC electronic devices that are usually considered safe with a low risk of electrocution, it is always better to be safe than sorry.

Therefore, here are some important safety tips to ensure that the job is done safely and efficiently:

1. Turn Off the Power: Always make sure the power is disconnected before performing any installation or maintenance work on the LED strip. This prevents electrical shock and potential damage to the power supply unit.

2. Use Proper Tools: Use insulated tools when working with electrical components to prevent short circuiting or injury. Make sure tape measures, screwdrivers, and other tools are in good condition.

3. Avoid Sharp Bends: Never bend LED strips at a sharp angle, as this may damage the LED or FPCB circuitry.

4. Check Voltage: Always check the voltage match between the LED strip and the power supply. Incorrect voltage may cause overheating or electrical damage.

Please Note: In some of the troubleshooting steps we suggest below, you will need to plug in and power up the power supply to complete the test. If you are unsure how to perform these tests safely, use caution and consult a professional.

Common Failures of LED Strip Lights and How to Solve Them

Power Supply and Connection Issues

1. The LED does not light up at all

Cause and Description: If the LED does not light up, it may be because the LED power supply is broken.

Solution: If you have more than one power plug board, please try to connect different LED power supplies to the same plug board to check whether it works properly. If it can’t work properly, it means your power supply is damaged and needs to be replaced with a new one.

2. The LED strip light can not be turned on

Cause and Description: You just unplugged the LED strip. Is it still on? Then you may have plugged it back in, but the LED strip light can not be turned on. This may be a poor-quality strip, or the power supply is not working or malfunctioning.

Solution: A poor-quality LED strip light is not worth your time; you can throw it away and buy a high-quality LED strip light. But before throwing away your LED strip light, please check if the power supply is working properly; most of the time, it is because the power supply is not working or malfunctioning. If you are not sure, take the power supply to an electronics repair store for a quick test.

If your light strip uses battery power, try replacing it with new batteries. Of course, this also applies to your LED remote control. Finally, check the cables; poor wire connections can and do cause the strip to light up abnormally or not turn on.

For more information about how to choose the right power supply, please read the blog: How to Choose the Right Power Supply for LED Strip Lights.

3. The whole LED strip does not light up

Cause & Description: When you connect all the components and connect the power supply to the LED strip, turn on the switch, but there is no response. What is the reason? First of all, the voltage of the LED strip and the voltage of the LED power supply may not be the same; secondly, the positive and negative poles of the LED strip are not correctly connected to the positive and negative poles of the power supply; thirdly, you have accessed an unsuitable LED dimmer or controller; fourthly, the connector of the LED strip is loose; finally, the power supply is faulty.

Solution: Make sure the rated voltage and rated current of the power supply are compatible with your LED strip. If your power supply is 12V DC, it is not compatible with a 24V LED strip. Check the label on the power supply, which indicates the output voltage. Then, check the LED strip itself; the input voltage is labeled at the LED strip connection point.

Make sure that the V+ and V- pole cables of the LED strip are properly connected to V+ and V- of the LED power supply. For beginners, this is probably the easiest mistake to make. LED strips and power supplies are usually labeled V+ and V-. Make sure that the connected cables are correctly connected to the corresponding polarity.

Per LED dimmers and controllers to match, you will need to first remove all optional dimmers and controllers and determine if the LED strip can be made to glow without the use of additional accessories. If the LED strip works properly, there is a problem with the dimmer or controller or with the connection between these accessories. You will need to check the connections or replace the dimmer or controller. Please note that the power must be on for this test, but do not connect a low-voltage DC (e.g., 12V/24V) LED strip directly to a wall socket at mains voltage (e.g., 120V/240V)!

Ensure that all connectors and wires are in place and not disconnected. Try tightening the screws on the power supply and then re-insert the LED strip into the solderless connector, making sure that the press is firm and that the connection points are making proper contact. Solderless connectors are usually a common point of contact failure.

If you have checked and ensured all the above steps and the LED strip still does not work, the power supply or LED strip may be damaged. Simply replace the power supply or strip.

4. The LED lights up and then goes out

Cause and Description: Sometimes LED strips will suddenly light up and go out. This may be due to the LED dimmer you have installed. These strips will not work with many inexpensive dimmers.

Solution: This problem can be solved by replacing the dimmer. Before replacing, find out which LED dimmer is best for your strip. If the problem persists, the plugs may be bad, so you should get a new set.

5. The LED strip has tripped

Cause and Description: There are two possible reasons for this. One is that your power supply may not be working. If the power supply isn’t working, your circuit breaker won’t be able to handle a lot of current at once. The other is that the circuit breaker does not have enough capacity.

Solution: If you think one of the power supplies is bad, you need to disconnect the circuit breaker and then try reconnecting the power supplies one at a time until the circuit breaker trips so you can tell which power supply is bad.

If the breaker still trips even though more than one power supply is connected and none of them are bad, the breaker is not capable of handling the input current, and you need to increase the capacity of the breaker. You will need to replace the breaker with one of greater current capacity.

6. LED strip connector does not work

Cause and Description: Sometimes you need a specific connector; RGB, RGBW, and white LED strips have different types of connectors. It doesn’t matter if they look different. You just need to make sure that you choose the right LED strip connector and that the connection points are making good contact.

Solution: The connection points of RGB, RGBW, and white LED strips correspondo 3-PIN, 4-PIN, and 2-PIN LED strip connectors, and you need to purchase the corresponding Connettori per strisce LED.

You just need to connect the copper soldering disk of the light strip to the copper part of the connector. Open the connector, and you can see the interface. After that, insert the light strip into the connector. It is important not to apply too much force. Simply insert the light strip into the connector on both sides. Also, you need to pick up the polarity of the connector.

And there are good and bad connectors. If the contact is good, the connector will click when you close it, indicating that everything is in place. If the cover doesn’t fit tightly, go back and put it back carefully.

7. The LED strip lights up only when I touch it

Cause and Description: You may have more than one LED strip installed. Some strips light up and work properly every time, while others do not. When you accidentally touch one of the strips that doesn’t light up, it sometimes lights up.

There are two reasons for this: First, most LED strips react to factors that cause problems in the network, such as WiFi, photovoltaic inverters, or inexpensive pulsed power supplies. Experts call this “capacitive coupling.” Essentially, it’s a transmission that may or may not be what you want. Secondly, the connection wire or connector is not making good contact.

Solution: Check the strip first to find out what the problem is. That way you can get to the source of the interference and eliminate it. Even better, replace the LED adapter with an EMC-certified LED power supply. This is much better than a standard power supply noise suppression filter.

Re-check the input connecting wires or connector portion of the strip to see if there are any pads coming off, loose connections, or no connections, etc. If there is any of this poor contact, reconnecting or fixing can be repaired on the strip.

8. The LED strip light can not be completely off or can not be turned off

Cause and Description: Sometimes the LED strip light is still on even if the socket switch is off. You quickly tried various methods to find out the cause of the irregular illumination, but you can’t figure out the problem. This could be a problem with the induced voltage.

Solution: Please move the LED strip to another location and perform some tests to find out the problem. There may be interference causing the lights to dim. Often, this can be fixed by simply replacing the switch. If the problem persists, you may need to install a new switch that is compatible with the LEDs, such as Z-Wave.

LED Strip Partly Does Not Light Up or Has Brightness Issues

1. The brightness of the LED strip gradually decreases near the end

Cause and Description: The brightness of the LEDs decreases at the end of the strip due to a voltage drop at both ends of the strip. Most common LED strips can be powered from one end for up to 5 meters without a significant voltage drop. (Some special LED strips, such as constant current strips, are available in lengths of up to 10, 15, or 20 meters.)

Solution: For the voltage drop caused by the reduced brightness of the end of the strip. There are two ways to solve the problem: (1) Separate the strips and connect two 5-meter strips in parallel to the same power supply; (2) Install a looped mains cable with a starter lead and an exit lead on a 10-meter strip and connect both cables to the same power supply.

For more information on voltage drop, please read the blog: Caduta di tensione sulle strisce LED: Cause e soluzioni.

2. One or more sections of the LED strip do not light up

Cause and Description: If your entire LED strip is lit, but you find that one or more of the 3 LEDs or 6 LEDs do not light up, one of the components may have a “broken circuit.” This means that due to a manufacturing defect or mechanical damage during transportation or installation, one of the LEDs or resistors in a section has become loose or broken, resulting in the LED in that section being completely disconnected.

Solution: If you are familiar with soldering methods, you can try to reheat the solder joints of each LED and component on that disconnected section. If you are not familiar with soldering methods, the best thing to do is to ask your supplier for a replacement (if they offer a warranty) or remove the faulty section by cutting the unlit LED segment directly along the cut line and then reconnecting the two segments together with a solderless connector.

3. In the same LED segment, only one LED is off, while the other LEDs are on

Cause and Description: The LED chip may have burned out, which can be determined by observing whether there are obvious black spots on the LED surface. Possible causes include static breakdown, an unstable LED power supply, excessive inrush current, or an insufficient resistance value of some LEDs. This is caused by problems with the internal PCB circuitry.

Solution: The best thing to do is to ask the supplier for a replacement if they offer a warranty. Or you can just cut the whole LED segment (need to follow the cut line) and then use solderless connectors to reconnect the two good segments together, thus removing the faulty part.

4. LED strip dimming over time

Cause and Description: If you notice the LED strip dimming over time, there are two possible causes to consider: a drop in the input voltage or a decrease in the brightness of the LED itself.

Solution: (1) Check the input voltage. Measure the input voltage with a multimeter to make sure it is within the expected range. If the measured voltage is lower than the rated value, the wiring may need to be corrected or the power supply replaced. A low input voltage will result in a decrease in the brightness of the strip. (2) Assess the condition of the LEDs. LEDs gradually lose brightness over time due to aging or defects. If you have ruled out an input voltage problem, you may need to replace the entire LED strip.

5. End of SPI addressable LED strip not illuminated

Cause and Description: SPI Addressable LED Strips are designed to control 1/3/6 LEDs via ICs on the strip; one IC = one pixel. Therefore, please make sure that the number of pixels that the SPI controller can handle is larger than the number of pixels of the SPI LED strip, and make sure that the pixel setting of the controller is correct.

Solution: Check how many pixels (IC) your addressable SPI LED strip has and check the number of pixels your SPI controller supports. If the number of controller pixels is less than the number of LED strip pixels, then you need to replace the SPI controller with one that supports more pixels; if the number of controller pixels is more than the number of LED strip pixels, then you need to check if the pixel settings of the controller are correct.

Color Showing Issues

1. RGB/RGBW LEDs show different colors in several small areas of the strip

Cause and Description: Is most of your RGB/RGBW LED strip working correctly, except for one or two segments within the cut point? For example, when you select “Orange,” a section within the cut point only shows green. This means that the red LED or resistor in that section is faulty. You can easily confirm this: If you set the strip to red, the LEDs in that section will not light up at all.

The simple reason is that one of the RGB/RGBW LED colors is not illuminating in that area, and the LED or resistor needs to be replaced. This can be caused by static damage, excessive bending and twisting of the strip, stepping on it, damage during transportation, cheap and poor-quality strips, or dry solder joints.

Solution: In most cases, the only option is to replace that portion of the strip. You can replace the entire strip. Alternatively, you can cut out the damaged section and re-solder the good section of the light strip, or you can use solderless connectors to attach it.

Before taking this step, you can try touching or pressing the LED/resistor on the faulty section. In the best-case scenario, you may see the LED come back on. In this case, the problem is a dry solder joint, and if you can solder, you can fix this light strip with a little re-soldering!

2. RGB or RGBW LEDs show different colors

Cause and Description: If all LED colors are normal except one, and this affects that color on the entire LED strip—for example, the entire red LED does not work. This would indicate a faulty soldering of the red V-cable to the strip PCB, a faulty red cable from the strip to the receiver, or a faulty or broken connection of the red cable to the receiver.

Solution: Check for loose cables between the power supply, the controller, and the strip, especially if the cables have been extended using terminal blocks. An effective test is to disconnect all extension cables and controls by connecting the power supply directly to the light strip.

First, connect the positive side of the power supply to the positive cable on the LED strip. Then connect the negative side of the power supply to the corresponding negative color cable on the strip. If both light up, it means there is a connection problem elsewhere. Then, gradually rebuild the system by adding the controller (and extension cables if you have them) to see which component is causing one color not to light up.

3. LED strips show inconsistent colors in some areas

Cause and Description: If you install a cool white LED strip and then see a warm white light in any area or it looks “off,” this is because the strip has been painted or something else. This usually happens when painters come in to paint a room and they don’t know there are LED strips in the room because they are hidden.

Solution: Depending on the amount of paint, sometimes your LED light strips can be retained. You can wipe the paint off the strip, but don’t use any water-based products, or you will damage the LEDs. You can also use a knife to carefully and cautiously scrape the dried paint off the LEDs, making sure the strip is off when you do this.

4. When I select colors for the RGB/RGBW strip, they are all wrong

Cause and Description: The wires on the RGB/RGBW controller are reversed. For example, if you connect the red wire to the blue terminal and the blue wire to the red terminal, when you select a color on the controller, the color mixing will not be done correctly, and the color of the lights you see will be different from the color you selected.

Solution: You must check the cables and reconnect any crossed cables to the correct terminals. If you have extended the cables using cable connectors, you must also check these connections.

Sometimes different cables may come into contact, producing unpredictable results. For example, if the red and blue cables are touching, you will need to separate them to ensure a pristine and interference-free connection.

5. The same color temperature of the LED strip, the light-emitting color is not the same

Reason and Description: Different LED strip light manufacturers have different tolerances for color temperature. Even if the color temperature is the same but the DUV of the LED is different, the luminous color will look different.

Solution: Usually, you need to buy the same batch and color temperature of LED strip from the same LED strip manufacturer. For wholesalers, you need to ask the strip manufacturer to use the same PIN number of LED beads to produce your LED strip from start to finish.

6. Reddish color at the end of the RGB strip when mixing white color

Cause and Description: The main cause of this situation is voltage drop. Since the RGB beads consist of red, green, and blue chips, the voltage required to light up the red chip is small (2.0-2.2 V). Due to the voltage drop, the voltage at the end of the LED strip decreases. As a result of the higher voltage required (3.0-3.2V), the green and blue chips will be less bright, but the red chip can be lit as usual, making the end of the LED strip look red.

Solution: Separate the RGB strips and connect two 5-meter strips in parallel to the same power supply, or lead the wires at the end of the RGB strips and connect them to the same power supply.

7. LED light strip stuck in a color

Cause and Description: LED strip lights stuck in a color problem can happen at any time. Most likely the LED controller is stuck. More specifically, the controller settings no longer work properly.

Solution: If your LED strip controller has a quick reset feature, the fix is easy. If your LED controller didn’t come with an instruction manual, here’s a common fix. First, connect all devices as expected. Then, plug in the power adapter, and after about five or six seconds, unplug it, and the strip light will go out. Repeat this process until the controller is restored to factory settings. In most cases, you will need five to ten steps.

Physical Damage, Overheating, and Installation Problems

1. The LED is too hot, almost burnt to the touch

Cause and Description: There are two possible reasons for this. Either your 12V LED strip is connected to a 24V power source, or there is a slight “short” in the strip. If you have an output cable, the positive and negative output wires may be touching each other, causing a slight short.

If the problem is caused by applying 24 volts to a 12-volt strip, the strip will still work. Since you are delivering more than twice the normal amount of power, they will look brighter than normal. The problem, however, is that this increases the risk of fire and causes serious damage to the LEDs (usually within a few hours).

If the problem is caused by a minor short-circuit situation, the LEDs can also be damaged, and even the smell of burning can be dangerous. Typically, a positive or negative short caused by PCB circuitry or soldering will immediately burn out one or more sections of the LED bank on the front of the strip the moment the power is turned on.

Solution: If you are using a 12V LED strip, you will need to purchase a 12V power supply.

Whether you think there is a “short circuit” or not, you need to check each strip carefully to see if there is any solder through the cable connections or wire contact. If there is, you can use a knife to cut through the solder or wire so that the positive and negative terminals are no longer in contact, or you can re-solder.

2. The LED strip has a burning smell when it is rolled up and lit up

Cause and Description: If the LED strip lights up while still on the supplied reel or while still coiled, then the heat buildup will cause them to get very hot and gradually burn or melt the reel.

Solution: When testing LED strips, always ensure that the strip is unrolled and never coiled in any way.

3. LED strip too hot to touch

Cause and Description: When you light up the LED strip for a while, the LEDs are very bright and feel hotter when you touch the strip with your hand. The LED strip will eventually get so hot that you can’t touch it. This means that the LEDs are overworked due to too much current, or you are not installing them in a location that dissipates enough heat. Cheap and poor-quality LED strips usually run the LEDs at full current and full power to achieve a low price and high brightness.

Solution: You may not be able to identify the problem without testing. It’s a good idea to test to see if there are any problems with the electrical system. If you want to find out why your LEDs are overheating, here’s how. Use LED aluminum profiles to dissipate heat; a simple aluminum profile will do the trick. This is because the metal will absorb the heat and make the LED strip cooler. If it is confirmed that the problem is the light strip, you need to replace the LED light strip with a good-quality one.

4. LED strip adhesive losing bonding power

Cause and Description: If your LED strips are not properly adhered to the surface, they may peel off over time or fail to stay in place. This can lead to a poor installation, which in turn can cause problems such as uneven lighting. This problem is usually caused by inadequate adhesive backing, exposure to dust, or improper surface preparation. Certain surfaces, such as wet or unevenly textured surfaces, may affect the adhesive’s ability to bond.

Solution: Before installing, make sure the surface is clean, dry, and undamaged. Use a soft cloth and soapy water to remove any dirt or oil. For better adhesion, you can use additional adhesive-backed LED strips or reinforce them with high-quality double-sided tape. If the adhesive bond weakens over time, consider reapplying the adhesive.

We recommend using a higher-quality double-sided tape, such as 3M VHB. For more information on how to choose a double-sided tape, check out our blog: Best Quality Adhesive Tape for LED Strip Lights.

Control and Dynamic Effect Problems

1. The LED strip remote control does not work

Cause and Description: When you assemble and test the LED strip and remote in the store, everything runs fine. Then, this strip was taken to someone’s home or workplace, and nothing happened, and the remote control broke. On top of that, the colors no longer change. And when you try to turn it off, it won’t turn off; in short, no matter what buttons you press, the remote doesn’t work.

Solution: The LED remote and receiver have a distance to receive the signal (usually within 5-10 meters), and sometimes you can easily forget the location or distance of the receiver. You need to try to move the sensor to eliminate this little trouble. If the problem is not a dead battery, you may need to reset the remote. You will then need to reassemble it with the light strip.

Also, you need to make sure that there is a good connection between the receiver, the power supply, and the LED strip as well. On the other hand, cheap universal remotes may stop working at any time. If this happens, look for and replace it with a branded remote control model that is compatible with your light strip.

2. LED lights do not blink or chase

Cause and Description: Modern LED strips usually have their own applications to control them. They are sometimes compatible with specific operating systems and sometimes with applications for all systems. Sometimes, even though you connect the light strip to power and WiFi, you can’t control its operation. So, it may take a lot of effort to solve the whole problem step by step.

Theoretically, there are two main reasons why a chasing LED strip won’t blink or chase. The first reason is the use of dimmers. The second factor has to do with the software.

Solution: If you are using a dimmer, remove it. Disconnect it from the power board, and the problem will go away. This is because the chase or blink functions do not apply to dimmers.

If you are not using a dimmer, you will need to reconnect the strip to WiFi. You must use an app or online program to find a network. The LED strip must then be connected to your cell phone to work together. Once this is done, you may need to recheck the settings. You will notice that the settings usually do not show any pairing information. Therefore, you will have to start over or ask for help.

Other Abnormal Phenomena

1. LED flickering

Cause and Description: If your LEDs flash in a regular, consistent sequence (e.g., on for 1 second, off for 1 second, then on again for 1 second), your power supply is overloaded. This means you have too many strips of lights connected.

For example, if you have a 10-meter-long LED strip with a total power consumption of 80 watts, and this strip is powered by a 60-watt power supply, the power supply will go into overload protection mode. This means that the power supply will turn on, then realize that it is overloaded, turn off immediately, and then repeat the cycle over and over again.

Solution: You can purchase a larger power supply (e.g., 100 watts) to meet the total power required, which is greater than the total power of all the LED strips. You can also split the strip and connect it to two separate power supplies that are identical to your existing power supply. On the other hand, your project may allow you to connect fewer strips to that power supply.

2. Flickering light strips in video

Cause and Description: When you have finally finished installing the LED light strips throughout your house, so you start to record video footage, you may suddenly notice a significant flicker in the video stream. This flickering, which is captured by the camera, is usually caused by the pattern of light waves emitted by the AC power supply driving the light source. If you can see the flicker directly with your eyes or vision, it is caused by a low-quality power supply.

Solution: Flicker captured by the camera can be resolved by simply using a mobile power supply. This is because the battery is powered by direct current (DC). Of course, this is not a permanent solution either, so purchase non-flickering LED strips and a high-quality non-strobe LED power supply.

If you witness flickering, check to see if the power supply is damaged or leaking or if you are using a cheap power supply. If so, replace it with a branded non-flicker source.

3. LED strip light buzzing sound

Cause and description: LEDs work by utilizing a principle called electroluminescence to convert electrical energy into light. When the current passes through the LED chip inside the strip, the LED chip will emit light. However, this current can sometimes interact with other electronic components or environmental factors, causing vibrations or audible hissing, humming, and noise. The most common causes are power supply problems or dimmer compatibility.

Solution: First, make sure the power supply or outlet is stable and functioning properly. A simple test is to use a different device in the same outlet to test if it is working properly.

If you are using a low-quality or underpowered power supply, consider upgrading to a higher-quality power supply. Choosing a power supply with a built-in voltage regulator will help mitigate voltage fluctuations and reduce noise levels.

Choose an LED Strip Manufacturer for High-Quality LED Strips

At SignliteLED, we pride ourselves on customer service and reliability. Quality and reliability are at the center of every product we craft.

LED strip lights manufactured by SignliteLED follow strict quality and reliability specifications to avoid the common problems mentioned above. Unfortunately, this is not the case with many other “cheap” LED strips on the market. Even if you follow the troubleshooting steps provided, some LED strip problems can be more complex and may even require professional assistance, and SignliteLED understands that problems can arise at any time, especially with inexpensive LED strips.

If you have a problem with an LED strip you purchased wholesale from us, please contact us immediately. Even if you have purchased your LED strips elsewhere, we will be happy to assist you and discuss replacement options.