How to Fix Radio Interference From LED Lights?

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Drivers are always complaining about the interference that LED lights cause, making it hard to listen to the radio in the car. This is a big problem, especially at night, because when your headlights are on, you won’t be able to listen to your favorite radio stations. So you may have to try to fix radio interference from LED lights.

But, it’s hard to figure out which LED lights cause radio interference. An AM radio can be a sensing tool if it has an antenna that can pick up on unwanted signals. After many years, only a few large ferrite cores remain.

This is the most straightforward way to solve the problem. The LED bulbs need to be changed out. The transformer of an LED light needs to be changed. It would be best if you used wires that are short and covered.

Here we will explain how to fix the radio interference from LED lights. Keep reading this article till the end!

What is Radio Interference?

Most radio listeners understand that radio signals are transmitted through the air. The signal is detected by your radio, but it is not limited to wireless devices or televisions that receive wireless signals. This is extra noise that helps you to avoid unwanted noises. These noises can be a humming, buzzing, or audible sound that is still annoying.

Because radio is a transmitted signal, the cause of this interference is something you can investigate. You must consider what is being heard, how frequently it occurs, and other obvious clues.

The majority of the time, this interference is caused by connected electronic power supplies close to your radio. These electronics can even be used in conjunction with other equipment that contributes to radio interference.

In a nutshell, radio signals operate on a specific RF (radio frequency) that ranges from 100kHz to 300GHz. Interference can be picked up if electronic equipment or other transmitters are near your radio. RFI (radio frequency interference) can be caused by other sources, just like anything else. When natural elements are present, changes in frequency can be heard.

Examples are solar flares, the electromagnetic disturbance of northern lights, and even lightning during a storm. However, not all these are ongoing and contribute to a problem with your radio equipment. The remainder of this article will explore methods for determining what is causing RFI and how to minimize and eliminate it.

Why do LED Lights Generate Radio Frequency Interference?

Most of the time, the LEDs are to blame for the interference in the car. There may also be interference from other lights in the area. Recent car models have a lot of LEDs in different places, like the front headlights, door lights, and overhead lights, as well as bars and spotlights that light up.

Your home’s LEDs can also interfere with your wireless signal, called radio interference. LED lights are not the only cause of the problem. The unit that feeds the LED is the source of the interference. “LED Driver” is often used to mean the power source for the LED (or sometimes, a Ballast).

LEDs work with a series of energy bursts that can be controlled. This is called Pulse Width Modulation, or PWM, and it is controlled by the duty cycle. A ballast or LED Driver sends power to an LED in short bursts. The rate of these bursts determines how many times per second an LED flickers.

During this process of flicker control, the Hertz ratio is turned into an electric signal. This signal is then picked up by the radio in the car or any other radio device. When this happens, the radio speakers will start to make a sound. Low-quality electronics, especially in the transformer, are another common reason for this kind of disruption.

The recessed lights are another thing that makes noise. This problem happens when the radio and recessed lighting are both on at the same time.

How do LED lights interfere with Your Radio?

The bulbs aren’t always the source of the problem, but if they are, here’s how to change them. The most common source of interference is the electrical ballast.

Surprisingly, it is not always the LED light bulbs themselves that are the source of the problem, but rather how they are powered. LED lights, as you may know, produce light by flickering hundreds or thousands of times per second.

The number of flickers is kept under control by an electrical ballast. Still, some of this energy can be converted into an electrical signal and picked up by your car’s radio.

How to Fix Radio Interference From LED Lights?

Here is this fixing procedure of your radio interference from LED lights!

  • Using an AM Radio to Locate the Source
  • Using Ferrite Cores
  • By Changing the Light Bulbs
  • By changing The LED Light’s Transformer
  • By Using Wires

Here are the details of this steps!

Using an AM Radio to Locate the Source

Use an AM radio as a sensor to find transmissions that you don’t want to hear. A VHF radio can also work with it.

The first step will be to determine where the noise is coming from. If we don’t know where the source is, we won’t know what to do next. You can skip this step if you know where the interference is coming from.

The easiest way to locate the source of the interference is to use an AM radio. It doesn’t have to be brand new, but it needs new batteries and volume control.

The setup is simple as well. Now you just need to find a station near the bottom of the dial. Make sure that the radio isn’t making any noise, even if it’s just static.

Your AM radio will act as a sensor and pick up all of the signals in the area if you do it right.

Make sure the volume is right. If it isn’t, you won’t be able to hear the source or figure out where it is coming from.

Now that we’ve finished setting everything up take the AM radio and put it near every LED light inside or outside the car.

Headlights, brake lights, fog lights, traffic signals, door lights, overhead lights, and other lights should not be ignored. Keep in mind that interference could come from more than one place.

Using Ferrite Cores

It is the easy and simplest way to get rid of the problem. They can be bought for a low price. It can be hard to put them on lights that are hard to get to, like up-high car lights.

Ferrite cores, also called ferrite chokes, ferrite beads, and EMI filters, are small parts that work simply. Wrap a ferrite choke around the wires that power the lights, and you’re done. The only bad thing is that you must use one for each LED bulb.

But you will see that the interference goes down steadily as each ferrite core is put correctly. It will go away completely in the end. But how do ferrite cores work, to begin with? They are filters that stop the high-frequency current or at least cut it down by a lot.

For LED lights of lower quality, a ferrite core will be needed. The lines that power incandescent lamps don’t need ferrite cores because incandescent bulbs can’t cause any kind of interference.

By Changing the Light Bulbs

If the LEDs you have now aren’t very good, this is a good idea. Go for well-known brands if you can afford them. In some situations, getting rid of the LED bulbs and getting new ones is better. This is especially true for interior lighting, where using a ferrite core can be hard or even impossible.

You must buy high-quality LED lights. They may cost more, but the cheaper ones will give you the problems you’re trying to avoid. Most LED light bulbs from reputable sellers meet the EMI suppression rules, which is exactly what you’re looking for. Many well-known brands on Amazon, such as Philips, Cougar Motor, BEAMTECH, and Osram. If you don’t know for sure that a brand is good, don’t buy it.

By changing The LED Light’s Transformer

Sometimes the transformer is the cause of the problem. As already said, the problem could be with the LED bulb or the parts that power the light. So, if you want to, you can replace the transformer in your LED light with one that blocks EMI better. If you do it this way, you won’t need a ferrite core. But it’s important to note that this method only works with low-voltage LED lights. For bulbs with a voltage higher than 12V, it is better to use one of the other options in this article.

Also, some LED lighting systems to have a transformer inside, which means, as we’ve already said, that you have to replace the whole thing. If the lighting system has an outside transformer, you can change it. Like bulbs, transformers need to be high quality to reduce interference. If you’ve done everything right, your radio should work fine with any station.

By Using Wires That Are Shorter and Better Protected

The interference won’t go away, but it might work as a fix. Even though this method won’t fix the problem caused by LED lights, it has been seen that interference is more likely to happen with longer lines. Because of this, we suggest using shorter wires to reduce the amount of interference. If this is not possible, you can use insulated cables.

Final Words

Typically low-cost, non-‘name brand products cause many problems associated with LED lights. Imported LED car headlights are always built with cheaper LED driver and power supply parts. Aside from replacing faulty parts that emit interference, the most affordable methods are usually the most cost-effective. So to get rid of any problems try to use branded products!


Here we have listed some questions about interference of radio from LED lights and some related questions. You can check them also!

AM or FM, which is more susceptible to interference?

Both of these signals are impacted by radio interference from LEDs. However, compared to FM radio, AM is more prone. It’s because FM transmits a stronger signal than AM, which uses a shorter signal.

Do LED Lights Interfere with Audio?

Both speaker noise and audio system interference are possibilities. The most frequent causes are a poor ground loop, radio frequency interference, or faulty wires.

Do Led Lights Give Off Radio Frequency?

LED lights emit a signal via an electromagnetic field between 400 and 600 THz. It happens much more frequently than with almost any home appliance.

Does the WiFi signal suffer from LED lighting?

LED lights, a sad fact, can disrupt the WiFi signal. The cause is that LED lights operate at a higher frequency than WiFi signals, ranging from 2.4-5GHz. Electromagnetic radiation that is essential to life occurs between 400 and 600 THz. Although it is not harmful, it does have the unwelcome propensity to emit electromagnetic waves that your WiFi can detect.

Why do LED lights interfere with my TV?

LED light bulbs can cause interference on your TV as well. You must either swap out the lightbulb for a high-quality model or attempt to diagnose the issue. Use EMI (electromagnetic interference) filters to shield your TV cables, such as a Ferrite core filter. As longer bundled cables behave like radio reception, you might also try shortening the cable that connects to your TV.

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