LED Headlight Bulb Keeps Blowing Fuse: 6 Problems & Their Fixes

Why is it that my LED headlight bulb keeps blowing fuse all the time? Below are some reasons why this happens, and what you can do about it.

Many people think that LED headlight bulbs do not fuse. If you think the same, here’s a surprise: the lights can always blow up. So, it would be best to learn about common reasons why these bulbs fuse out of nowhere. Continue reading to learn more about this.

LED Headlight Bulb Keeps Blowing Fuse

What Are LED Headlights, and How Do They Work?

Light Emitting Diodes, commonly known as LED, are used in houses and hotels, but only a few people know that they also make the headlights of cars these days. These bulbs might be more expensive but cause less emission and reduce fuel consumption.

These lights are semiconductors that allow current to pass through them to do its job, giving out the light. They are simple to use and are, thus, expected to work for a long time.

However, they can blow a fuse due to certain shortcomings or issues discussed below.

Why LED Headlight Bulb Keeps Blowing the Fuse, And How To Fix The Problem

There can be several reasons why even a recently purchased LED headlight bulb may blow a fuse. For your perusal, we have listed the leading causes behind why these bulbs blow so frequently. Check them out below.

Loose wires

When the wires connected to the bulb holder are loose, it disrupts the regular flow of energy into the bulb, increasing heat. A typical bulb filament is designed to carry only a specific temperature, which, when it crosses the heart limit, leads to blowing a fuse.

Loosen wires can be dangerous in other ways too. For example, when driving, you may need the headlight switch to cross a dark tunnel. If the bulbs are fused, it can lead to a gravely unwanted situation.

You must also ensure that the bolts are fitted tightly for the bulb to function correctly. If you notice vibrations in the headlight, cracks in the mounts, or burnt or melted connectors, make sure to replace them with new wires. This way, you can reach the source of the problem and eliminate it altogether.

LED Headlight Bulb Keeps Blowing Fuse

Problematic voltage regulator

A voltage regulator, also known as a voltage stabilizer, is the equipment you can either find connected to the alternator or fitted separately. Electrical needs to keep the headlight bulbs from blowing a fuse since it holds in or keeps a check on the maximum voltage limit to run through the electrical apparatus and ensures that all the system components can utilize it.

If the regulator has a problem, it will show up through voltage spikes, making the electrical system unstable, which naturally leads to a headlight fuse.

If your regulator has been showing voltage spikes intermittently, you can check whether it’s faulty. Follow the steps below to check the same.

  • Get your hands on a multimeter. If you don’t have one, you can buy the same from the market for $12.
  • Now, take the favorable red terminal safety from the battery, if any, from the bonnet and set the meter to 20 DC volts.
  • Shut off the lights and ignition before you go to the next step.
  • Next, connect the red or positive lead to the positive terminal and the black or negative lead to the battery’s negative terminal.
  • Ask a friend or family member to check the neutral and turn on the engine.
  • The battery is charging if the multimeter reading rises above 13.8 volts while the vehicle runs slowly.
  • Ask the friend to increase the speed of the engine up to 1500 – 2000 RPM, check the multimeter’s reading, and see if the regulator limits the amount to 14.5V.
  • If it goes beyond 14.5V, there is a fault with your vehicle.

If your voltage regulator works fine, check and replace the alternator belt since an obsolete or poorly manufactured belt can lead to power surges. You can also install resistors to the beam circuits. However, you should first perform the regulator test before replacing the belt.

Excessive and immoderate vibrations

Halogen headlight bulbs do not go well with excessive and immoderation vibrations in the filament. You can easily check for vibration by ensuring that the LED bulb’s spring is in place. If the chip moves, the vibrations are high, leading to a blown fuse.

Additionally, you should ensure that the headlight is fixed tightly on the main equipment as well. Some examples of such equipment include suspension springs, wheel balance and bearings. Remember that any tool that may give rise to vibrations must be checked to make sure that the headlight bulb is functioning properly, or else it will fuse, and you will have to spend a good number of hours changing them.

LED Headlight Bulb Keeps Blowing Fuse

Cheap or poor-quality of bulbs

It may sound cliche to you, but poor-quality bulbs are one of the main reasons for a blown fuse. Poor quality or low-brand bulbs do not work well because they lead to excessive vibrations (as discussed above).

Additionally, they commonly comprise wire filaments made from the thinner gauge of tungsten, which is cheap and, thus, low quality. These wires can stop working within a few hours after installation and, thus, are of no use.

So, always make sure to buy premium brands of bulbs for their long life and also save yourself from the trouble of the frustrating task of changing bulbs now and then.

Excessive vibrations coupled with bad-quality wire filaments lead to the easy blowing of the fuse box, especially if you also have a second-rate regulator.

Condensation in the headlight

Excessive condensation in the headlight can significantly reduce the life and quality of incandescent bulbs. If the headlight is condensed more than required, it starts causing fluctuations and electric shocks, which deteriorates the bulb’s life.

The headlights must be well-ventilated from top to bottom to remove excessive condensation. Everything must be free from excessive moisture, from tubes to holes, so there is no space for immoderate condensation.

The lights’ tubes are designed to allow a small amount of air and moisture to dissipate the heat, which gets out through the same hole or tube. However, it can also lead to excess moisture, so proper ventilation is necessary.

To keep condensation away from the headlight, ensure that the seal around the bulb’s lenses is intact and the bulb covers are mounted correctly on the headlight. In such scenarios, the condensation is higher than usual and can lead to severe damage to the white bulb.

To avoid excessive condensation, you must avoid buying poor-quality headlights. You will notice excessive condensation within a few days when you buy low-quality lights. We want to remind you that a bit of condensation is expected.

However, if you often see big drops of water at the bottom of the headlight, it is a sign of excessive and uncontrolled condensation and should be checked.

Holding or touching the bulb at the time of installation

Only a few people know that touching halogen bulbs can lead to uneven heating, which is unsuitable for the headlight. These bulbs get heated within a few seconds and need the same temperature throughout their surface to work well and have a long life.

However, it is not easy to fit the bulb without touching its surface with your hands. The other thing is that your hands are already full of dirt and skin oil by the time you reach the stage of fitting the bulb. Even though it is rare, the dirt of your hand, if left on the bulb’s glass, can cause them to explode, resulting in permanent damage.

Thus, it is recommended to wear latex gloves and touch the metal base at the installation time. If you doubt your abilities, it is better to hire a professional to do the job, no matter how easy it seems to you in the first place.

LED Headlight Bulb Keeps Blowing Fuse

Frequently Asked Questions

Why do my headlights keep blowing a fuse?

There can be many reasons behind headlights blowing a fuse again and again. Still, it is mostly because of low-quality bulbs, faulty voltage regulators, loose wires, and excessive vibrations.

Do LED headlights need a fuse?

Not all LED lights need a fuse, but the headlights need at least a 2 amp fuse to work. A normal headlight uses a beam of at least 55 watts. So, you are good to go if you use a 10A fuse for your LED headlights.

Can LED light cause short circuits?

LED lights can cause short circuits if there is excessive condensation inside the bulbs or the lights are mixed with CFL lights. Short circuits can also happen if there isn’t enough power supply to the LED bulbs.

Can LED bulbs fuse?

Even though it is rare, LED bulbs can still fuse for many reasons. If the chip inside the bulb fails to convert the current draw to direct current, a high amount of electricity can blow up the bulb.

LED Headlight Bulb Keeps Blowing Fuse

Wrap Up

From checking the wiring harness to getting rid of bad ground wires, it can be a task to stop LED headlights from blowing a fuse. And so you must have a good knowledge about the common reasons that can lead to a blown fuse and ways to prevent the same.

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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