Why Does My Car Stereo Fuse Keep Blowing? 3 Ways to Fix This.


You have had it. You promised yourself that if your car stereo fuse blows one more time, you’ll do everything in your power to figure out why it keeps blowing and look for ways to fix it. So, now, you’re here and ready to find the answers and attempt the repairs.

Your car stereo fuse keeps blowing because your fuse features an incorrect amperage rating, your wires short cuts, or your stereo suffers internal damage. You can fix this by using the correct fuse, replacing your wires, or repairing your radio.

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Tip: If you are finding often blown fuse, you have to investigate the issue. To start the work on the radio and investigate it further, you need more fuses of the same amperage and do not replace the current blown fuse with the stronger one. That may cause permanent damage to your radio.

When you are searching for the replacement, check out my favorite car audio fuses on Amazon.com. 

In the article below, I will show you why your stereo frequently blows fuses and how to fix this issue.

What is a car stereo fuse, and how does it work?

Let’s understand what a fuse is and how it works, and then we can better understand what could cause them to blow in your car stereo.

A car stereo fuse is designed and works just as any other fuse would. It is an electrical safety device that protects an electrical circuit by providing overcurrent protection.

The main component that a fuse is based around is a metal wire or strip that melts when too much current flows through it. When the metal wire or strip melts, then the current is interrupted. This is the entire premise of a fuse and how it works. It is designed to cut off a circuit and save your electronic devices that could not withstand large amounts of current.

why car radio fuse blows

One thing to note is that a fuse is regarded as a sacrificial device (this means it is made to be broken and replaced).

Fuses are relatively inexpensive, and they are much cheaper than having to replace your top-end electronic equipment like your car stereo.

Many different fuse designs feature specific current and voltage, response times, and breaking capacity depending on their application.

What types of car stereo fuses are there?

There are three main types of fuses that are designed and are used in-car audio systems. Knowing these fuse types will also help explain why the fuses in our car stereo system keep blowing.

Cylindrical fuse (AGU & AGC)

These are common types of fuses that you will find in-car audio. Additionally, there are two sub-categories of cylindrical fuses, namely AGU and AGC cylindrical fuses.

  • AGC fuses are lower current versions of the high current AGU fuses.
  • AGU fuses are larger, and they have an amperage rating between 30 amps and 80 amps.

Blade fuses (ATO, ATC & ATM)

Blade fuses are contained within a fuse holder, and they are sometimes referred to as Maxi-fuses.

There is little difference between an ATO and ATC fuse except that the C stands for closed (the element is within the fuse’s housing) and the O stands for open (the element is open to the atmosphere and subject to the environment). An ATM fuse is just the smaller counterpart of the ATC fuse.

ANL Fuse

ANL fuses are also known as wafer fuses and are very common in-car audio. The amperage rating for these fuses is from 35 amps up to 750 amps.

Why Fuses Blow

Fuses blow when too much electric current runs through them. They act as pawns for your car’s bigger electrical components. They melt or burn when an electrical overflow occurs to prevent huge damage from occurring within your other car components and keep you safe from possible fires.

You’ll find it an annoyance to learn that car stereos often blow fuses. However, it may also offer you some relief to realize you’re not alone. 

Three reasons prevail when a stereo repeatedly blows fuses:

  • You’re using fuses that don’t fit your car’s fuse requirements. This means your fuse may possess the wrong amperage rating. Alternatively, there’s a chance you placed the fuses incorrectly.
  • You need to replace your wires with new or more appropriate ones. Sometimes, wires fray or develop eventual cuts here and there. Meanwhile, at other times, you may need to seek sturdier cables that can handle the currents produced by your car.
  • You may need to repair your car stereo or install a new one. When your stereo keeps blowing fuses, it may mean that its underlying cause has something to do with the stereo itself rather than your fuses or wirings.

Use the Correct Fuse

You were in a rush, so you decided to skip a few steps when you replaced your fuse, such as reading your car’s owner manual. Alternatively, you may have simply decided that you’ll just use any fuse you find. Then, after those instances, you forgot about them and kept replacing your fuses with inappropriate ones.

Of course, that scenario led to a constant fuse-blowing problem for your car stereo. You may not realize you’re using the wrong fuse yet, but you’ll notice your fuses keep blowing. The simplest way to figure out if you’re repeatedly using an incorrect fuse is to check your owner’s manual and compare your old fuse to the manual’s required fuse.

Before you solve this problem, you need to look at your car’s manual. The easiest way to find the section that contains car stereo fuse information is to flip over to your manual’s index. Then, seek out fuses, and find a car stereo. 

You’ll find that section filled with all the information you need regarding your car stereo’s fuses, and this includes diagrams and fuse specifications. The diagrams guide you on the fuse placement and labels, while the fuse specifications indicate the ampere of your fuses.

You’ll generally find the required amperage rating for each fuse already indicated on the fuses themselves through the numbers written on top. 

The specified ampere serves as a guide to indicate that it’s the maximum amount of power your fuse can handle before it receives damage. Hence, incorrect amperage results in your car stereo repeatedly blowing your fuse, so you must replace it with the correct one. 

However, note that it’s not wise to get a higher amperage rating than your current fuse if you’re tempted to do so. If you opt for a higher amperage rating than necessary for your stereo’s fuse, you’re weakening your circuit’s link in protecting your car’s other electrical components.

This solution works with improper fuse replacements as well. By using the manual as a guide, you can set the proper fuses to the correct locations. Sometimes, your car stereo keeps blowing your fise simply because of incorrect fuse placement.

Replace Your Car’s Wirings

You may find this as a surprise, but there are times when your car’s wirings are at fault instead of your stereo or fuse. The common cause related to wirings for a car stereo that keeps blowing its fuse is fraying wire insulation.

Your fuse will blow whenever the frayed wire’s exposed part touches your car’s metal frame or ground surface. This causes a short and, in turn, damages your fuse. You’ll often realize that this problem won’t go away until you’ve done something to prevent the wire from touching the ground.

You can diagnose this problem by physically observing your wires. When doing so, pay special attention to your drilled wire holes and any other areas under constant motion and exposure, such as your doors, trunk components, moving panels, and engine compartment.

So, you’ve done a thorough inspection and figured out that one of your car stereo’s frayed wire constantly blows your fuse. The solution to this depends on the extent of your wire’s damage.

For example, if your wire only possesses a small cut that peeks once in a while, you can get away with using electrical tape to fix it. Meanwhile, a bare wire needs trimming to enable the insulation to work. However, if all else fails, you can always simply replace your wire.

Repair or Replace Your Car Stereo

When the wirings and fuses themselves aren’t at fault, only one component remains to be checked, and that is your car stereo.

So, think back to when your car stereo started blowing your fuse. Did you recently install your car radio? If not, how long has it been since your stereo was checked for damages?

Sometimes, car stereos simply wear off over time. They can suffer internal damage as the car moves about and shakes its components. Similarly, you may have them connected the wrong way, and this results in their eventual damage.

Meanwhile, there may be times when your stereo installation goes wrong. You may not even be aware of it when this happens. By then, the damage within your stereo may worsen before it shows signs like blowing fuses or glitching, and malfunctioning.

You’ll know you’re facing this problem when your car stereo blows your fuse as soon as you put it in. When this happens, your solution is to fix your stereo by taking it to your local stereo shop or replace your whole stereo if the problem is unrepairable.

How to Replace a Car Fuse

If you’re unsure about the steps to replacing your car fuse, here they are:

  1. Find the blown fuse.
  2. Check your owner’s manual for the fuse’s requirements.
  3. Obtain a fuse of the same size, build, and amperage.
  4. Remove the blown fuse from the compartment and insert the new one.
  5. Ensure that the new fuse is plugged as deep as it can go.
  6. Place the fuse compartment back to its spot.

Final Thoughts

Three main culprits are prevalent when your car stereo fuse keeps blowing:

  • First, your fuse features an incorrect amperage rating,
  • Second, your wire’s insulation needs repairs, 
  • Lastly, your stereo suffers internal damage.

You’ll need to figure out the correct fuse for your car stereo and obtain it for the first issue. Then, replace the blown fuse with the correct fuse, and your problem should go away. 

Meanwhile, you can solve the second and third issues by either repairing the offending components or replacing them.

Martin

Welcome to ImproveCarAudio! I am Martin, and I love to write about everything related to car sound systems. I strive to provide the most accurate and helpful information about car audio through extensive research, as well as my experience with car audio installations.

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