9 Signs of a Bad Car Amplifier

9 Signs of a Bad Car Amplifier

If you are a big music lover but new to the car audio system, it might confuse you to identify the signs of a bad car amplifier or predict the kinds of issues it starts showing with time. 

Due to constant use for a long time, the amp shows various problems, but if the signs are left unfixed, it may get terrible, and you’ll have to replace an amplifier with the newer one. In this blog, we will explore the common signs that indicate a bad car amplifier and what steps you can take to resolve the issue.

What are the common causes of a blown car amplifier?

A blown car amplifier can occur due to various reasons, and here are some common causes:


One of the primary causes of amplifier failure is overheating. Amplifiers generate heat during operation, and if they are not properly cooled or ventilated, the excessive heat can damage internal components, such as transistors or capacitors. Insufficient airflow, running the amplifier at high volumes for extended periods, or operating the amplifier in a confined space can contribute to overheating.

Incorrect Wiring

Incorrect wiring or connecting speakers with an impedance that the amplifier cannot handle can lead to failure. If the speakers are wired incorrectly, causing a short circuit or mismatched impedance, it can strain the amplifier and potentially damage its circuitry.

Power Surges or Voltage Spikes

Power surges or voltage spikes, often caused by faulty electrical systems or improper installation, can damage the amplifier. Sudden increases in voltage can overwhelm the amplifier’s components and cause them to fail.

Blown Fuses

Amplifiers have internal fuses that protect the circuitry from excessive current flow. If the amplifier is subjected to a power surge or the speaker wires short-circuit, the fuse may blow, resulting in a loss of power or complete amplifier failure.

Improper Gain Settings

Incorrectly setting the gain levels on the amplifier can cause distortion or clipping, damaging the amplifier and speakers over time. If the gain is too high, the amplifier may be pushed beyond its capabilities, leading to overheating and eventual failure.

Age and Wear

Like any electronic component, amplifiers can wear out over time due to regular use and aging. The internal components may deteriorate or become less reliable, leading to performance issues or eventual failure.

We know you love your amplifier so much, but if it starts showing any of the 9 signs we’ve enlisted below, you will need to figure out the problem either on your own, or you probably need a technician’s help. 

A car amplifier is an essential component of a car audio system, responsible for powering the speakers and delivering high-quality sound. However, like any electronic device, amplifiers can experience issues over time, impacting their performance and audio output. Recognizing the signs of a bad car amplifier can help you diagnose and address the problem promptly, ensuring an optimal listening experience.

The 9 Common Signs of a Bad Car Amplifier

1. The amplifier fails to turn on 

That’s annoying! Even if it failed to turn on several attempts, there are certain reasons for that, it may have gotten old, maybe it has got a loose connection, and maybe due to the poor grounding. 

While bad grounding is the most common issue that doesn’t let the amp turn on. But the commuters fail to identify the root of the problem and call the technicians to pass the buck. 


Signs of a Bad Car Amplifier - The amplifier fails to turn on


But this is not always due to a major problem; some minors can be fixed without any help. We advise you to check first – If the wires are not broken if it is not mounted on the non-conductive place, fuses work fine, cables are not torn, cables are connected tightly, and the amplifier is getting enough voltage to run. 

The wires that power an amplifier directly come from the radio; make sure the radio is on for the amplifier to turn on. 

On the other hand, if it is grounded well, but the amplifier is still not turned on, then seek technician help, there must be some major issue that needs to be figured out. 

Read more about – How to Turn On an Amplifier without a Remote Wire?

2. Overheated Amplifier

The common sign of the bad amplifier is it gets overheated more often and then shuts down. If you are facing the issue quite often it may be due to the following reasons:

  • Poor grounding 
  • Operation for long hours
  • Low-quality amplifier often gets overheated frequently
  • Extremely high bass levels 
  • Poor connection 
  • High voltage 
  • Blown speakers
  • Faulty speakers 
  • Poor ventilation inside the car
  • Speakers are near to the base of the car
  • Speakers are connected to the low impedance

Frequent overheating of an amplifier may lead to permanent damage, never ignore it. 

To save your amplifier, make sure the bass levels must not reach the maximum values, the amplifier is grounded correctly. 

Always invest in the quality amplifier, and speakers should not be placed near to the car chassis as the amplifier will endeavor to power the speakers.

Also, the wrong size power cables and grounding have to be 8 gauge or above; otherwise, it will lead to overheating. 

If any of the speakers is blowing, disconnect it. If the cause is diagnosed, turn it off until the issue is solved.

9 Signs of a Bad Car Amplifier

3. The amplifier turns on repeatedly

It sounds like a scene from a horror movie, but don’t worry, the cause is different in real life – it’s a technical error! 

If an amplifier continuously gets turned on and off repeatedly, then there may be any of mentioned reasons for that:

  • Loose connection
  • Poor grounding
  • Not enough voltage supply
  • Power source is not tightly connected
  • Excessive heating and then tripping
  • Wrong size of the fuse connected
  • Reversed polarity 
  • Grounding is not done on the metal, clean, and rust-free surface. 

But if everything works fine, and nothing is getting problematic from the list then you may need to seek professional help, but if there’s a grounding issue, if the amp is poorly grounded, then you’ll be hearing a clicking noise coming out of speakers, fix grounding to get rid of the problem.

Learn more about – How To Fix Car Stereo That Turns On and Off Repeatedly?

4. Amplifier Blows Fuses

Fuses don’t require any reasons to blow, but that’s frustrating for the drivers when the amplifier fuse keeps blowing frequently. 

You may need to replace the fuse to solve it. But there are the following reasons why the amplifier keeps blowing the fuses.

  • Speakers are connected to the lower impedance 
  • Due to the wrong fuse size. 
  • Succession for many hours
  • Long hours of current supply 
  • Improper grounding of the amplifiers 
  • Damaged speaker wiring 
  • Low-quality cable’s wires
  • Small wires 
  • Poor-quality Amplifiers

Though the reasons for the blowing of the fuses are numerous, it all depends on how the wires are connected. 

Many efficient amplifiers are manufactured with built-in fuses that are relatively more advanced and struggle to prevent damages. 

They are blown often to stop further damages to the amplifier. If the amplifiers are professionally designed, they must have an inline fuse because an amplifier’s power cable is connected directly with the battery itself, which works fine.

But if there’s nothing from the mentioned list, replacing fuses with the newer one would help!

5. Excessive Whining, Buzzing, and Humming Sounds

Continuous whining, buzzing, and humming sounds can end up in the terrible drive.

To solve the problem, you will have to find out the root of the cause, check each potential cause. 

Check the cable wires and the patch cable first. If the cables that are connected to the amplifier are placed close to the ground wiring or main power unit, then the interference might occur, and it’ll produce noise. 

However, fixing the problem is easy; you just need to reroute the wire but finding the cause is the time taken. 

If you cannot find any issue with the cables, then unplug the speakers from the unit and check if it continues to produce noise, then it may be a grounding issue.

While there are some more causes of the distortion:

  • Bad antenna cables 
  • Bad-quality amplifier
  • Improper installation of an amplifier/ cables/ speakers 
  • Wrong mounting of an amplifier 
  • Defected amplifier 
  • Problem with the power unit
  • Poor ground connection

Once you have figured out everything mentioned but the noise doesn’t fade, then possibly it’s your amp that needs the technician’s assistance. 

6. Weak Bass Output

Your ears are yearning to dance on the favorite bass, but they can’t. 

At high volume, subwoofers may cut out, and the problem generally lies with an amplifier and sometimes with the subwoofer as well. 

Once the cause is ruled out, it gets easier to solve it. 

There are some obvious reasons for the weak and inconsistent weak output, we’ve compiled some for you:

  • Amplifier clipping 
  • Lower power input 
  • Poor wiring of subwoofers and amplifier 
  • Amplifier overloading 
  • Incorrect equalizer’s setting 
  • Radio overheating 
  • Amplifier overheating 
  • Poor-quality speakers 

Once you have fixed everything mentioned, but it still sounds weak or inconsistent, you may need to replace an amplifier. First, seek professional help and final confirmation one more time.

Before having a new amplifier, replace the subwoofer with another one to find the real culprit. 

7. Burning Smell

This often freaks the driver – the burning smell, where it is coming from? 

Well, there’s nothing to get freaked out but yes, it can be your amplifier trying to scare you. 

At the high sound volume, if some burning smell enters your nostrils, the amplifier cannot stand the high volume. 


Signs of a Bad Car Amplifier - Burning Smell


Maybe it’s not operating correctly, malfunctioning, or may be mounted in the wrong way. 

Once you smell the electronic burning, immediately shut it down until it gets cool, and then don’t make the volume go too high for it to cope. 

Besides that volume limit, there might be some more causes you want to know; we have mentioned some below:

  • Long hours running time 
  • Improper wiring 
  • Excessive overloading and overheating of an amplifier 
  • Speakers need more power to produce sound 
  • You’re listening to strong bass at high volume
  • Poor grounding
  • Wrong mounting of an amplifier 

Bad quality amplifiers always end up with a burning smell because they consume more energy; however, most of it is utilized in the production of sound while a portion is used to generate heat, which makes it overheated and begins to smell like burning. 

So always make sure to buy an amplifier from the trusted sellers, even if you have to do some research before purchasing, go for it, and read out some customer’s reviews to find if it’s the one you are looking for or not. 

8. Speakers stop making sound

Every device is connected through cable wires so are speakers connected to the amplifier. 

But if the car’s sound system stops producing sound, find the cause, unplug speakers, and attach them with another music source like your CD player or other, see if they make sound or not. 

If they don’t, consider replacing it with the new set but if they do, then the hidden culprit is your amplifier or maybe the broken cables. 

Don’t rush it; check everything for satisfaction first. 

Speaker doesn’t produce sound for the following reasons:

  • Cables are broken that carry sound signals to the speakers. 
  • Amplifier could not transfer enough power to generate sound. 
  • Amplifiers are defective or old to make speakers functional.
  • Amplifier is overheating.
  • The system has been running for a long time, and it tripped to get cold. 

Though there may be several reasons why speakers stop working, a few of them are due to an amplifier, while detection is easy with the signs mentioned. 

You can also read : How to tell if a subwoofer is blown?

9. Subwoofers make unusual noises

If the subwoofers are overpowered or underpowered, in either case, they start producing weird sounds. 

You may need to invest some time to figure out the cause. Maybe it is because the speakers’ enclosure didn’t connect with the subwoofer correctly; speakers are mounted wrongly at the wrong place. 

If the air is released, it will produce weird noise, but positioning speakers to the right place will help. 

Check all the wires extending from an amplifier to the speakers, and they must be intact and unbroken.

Also, make sure that the impedance of the subwoofers has to match.

Video Credit – HowcastTechGadgets

What are the known benefits of Subwoofers and Amplifiers? 

A car sound system cannot be completed without subwoofers and amplifiers as they are capable of harvesting the following benefits:

  • They give sound more clarity. 
  • They are efficient in generating better audio.
  • If you are a bass lover, subwoofers enable you to play around with different options until you get the desired results. They give you access to the lengthy and robust bass.
  • Amp comes with the options to set customize sound, volume, and pitch as you want to listen to.
  • They help you get an easy escape from the boring old music devices. 
  • Modern models of amplifiers and subwoofers are way more attractive, no matter how old your car is, but if you buy one of the newest amplifier models, it looks mint!
  • Modern designs come with modern features. They have an endless number of sound effects to conceal the original audio for better results. 


Amplifiers and subwoofers make the backbone and spine respectively of a car audio system. Still, they get damaged over time affected by several factors that have been discussed in the blog. 

Although little care is always required to restore the efficiency and to get the maximum advantage of it. I hope you’ve found the blog helpful!

About Brenda Smith

Brenda Smith is an Audio consultant and part-time automotive content writer. She has an Audio engineering degree from a reputed university of Tampa, Florida. Being a great audio enthusiast, she works with her audio consultation startup and writing automotive content as a part-time writer.

Check Also

How Can You Wire a Car Stereo Without Harness?

How Can You Wire A Car Stereo Without Harness?

You can wire your car stereo with as little effort as possible! The basic thing ...

Leave a Reply

Your email address will not be published. Required fields are marked *