how to repair car amplifier no sound

How to Repair a Car Amplifier With No Sound: All You Need to Know About Your Amplifier

Taking drives in our car can be boring sometimes, but thanks to the car amplifier, we can spice up our trips. The amplifier enables us to enjoy music and other audio content to add fun to our rides.

However, the amplifier is an electronic device, and like all electronic devices, it is prone to damage. Depending on the problem, there are different approaches to fixing your car amplifier. You can fix the power wires, ground wires, blown fuses, speakers wires, and other internal components no matter what has sustained damage.

Today, we will show you all you need to know about your car amplifier, what can prevent it from producing sounds, and how to repair a car amplifier with no sound. Follow us through this read, and get your car amplifier running in no time.

What is a Car Amplifier?

The car amplifier is the audio unit responsible for loud audio output. Your car’s sound system comprises three key systems: the main radio unit, the amplifiers, and the speaker.

Audio output is primarily generated from your radio unit, and it is also the unit that allows you to connect an auxiliary cable and play music from your phone. However, the sound output from the radio unit is very low, and the sound frequency is insufficient.

An amplifier is included in the setup to compensate for the radio unit’s low sound frequency. The amplifier is categorized into the pre-amplifier section and the power amplifier.

The preamplifier section is the input area of the amplifier, and it is responsible for collecting the low frequency from the head unit. The signal collected from the preamplifier is transmitted to the power amplifiers.

The power amplifier makes up the second part of the amplifier unit. It is responsible for strengthening the weak signal. The amplifier is usually connected to the subwoofer, and they produce a nice bass in your sounds.

Finally, the amplifier is connected to speakers around the vehicle. The amplifier sends the strengthened sound signal to these speakers, and they produce high-quality sound with regulated frequencies.

Different things can cause your amp to stop producing sound, and sometimes the problem is not actually with the amp. First, we will show you the common tools and the methods you need to repair an amplifier. Later, we’ll show you some common problems people experience and how to deal with these issues.

How to Repair a Car Amplifier with No Sound?

A open amplifier

If you’re not getting any sound from your car’s sound system, there is a good chance it’s the amplifier or the speakers. First, you need to confirm the source of the problem. If you’ve tested your speakers and you’re confident that they are working perfectly, you can check the amplifier.

To check the amplifier, we have prepared some basic tools that will make your job way easier:

Tools Needed to Repair Your Amp

To save you time, carry these tools with you when fixing your amp. If you don’t have them, you can run to your supply store and get them, or you can borrow them from a friend.

Soldering Iron

A soldering iron is a common tool used to join pieces of metal together. It will come in handy if you need to replace or remove a part of your amplifier.


There is a chance you will need to remove the panel of the amplifier, and it is screwed tight. A screwdriver will be handy if you have to deal with the screws. Philip screwdrivers are the best choice because the screws used are often star-head.

Electric Contact Cleaner Spray

This spray is used for cleaning electrical surfaces, and it is safe and efficient.


A multimeter is one of the most important tools to fix your amplifier. The multimeter is used for reading various forms of electrical parameters such as resistance, voltage, and current.

You will need the multimeter for testing different parts of the amplifier.

Other Tools

  • Wire stripper
  • Nose pliers
  • Allen key set
  • Knife

How to Repair the Amplifier?

To repair the amplifier, you first need to confirm the source of the problem. Once you’ve confirmed the source of the problem, you can attempt to fix it with these simple methods below.

Confirm if the Amp is the Problem

We mentioned earlier that your car’s sound system comprises different parts. The problem might not be with the amplifier. There is a simple way to confirm if the problem is from the amplifier.

First Step

The first step is to reduce the volume and power of the amplifier. Give it some minutes or a few hours to cool down before you start probing.

Second Step

After the amplifier has cooled, you can start the investigative checkup.

You can check two things easily to confirm if your amp is the source of the problem.

You can check the power supply and the sound output. These two don’t require dismantling your amp. From testing these two things, you can easily tell if something is wrong with your amplifier.

An LED indicator comes on when the amplifier is on, and you can easily use this to check if there is a problem with the power supply. If the light does come on, you can rest assured that there is nothing wrong with the power supply.

After confirming the integrity of the power supply, the next step is checking the sound output. If you can hear sounds coming clearly from the amplifier, it means it is not the source of your problem. On the other hand, if no sound comes from the amplifier, it indicates something is wrong inside.

Check for Potential Internal Problems

Repair Amplifier

Once you’ve confirmed that the amplifier is the problem, you can go ahead and open it to check for the source of the problem. You will need the screwdriver we mentioned earlier to open up the back panel and take out the chassis to get to the circuit board.

Some things to look out for include:

Blown Fuse or Transistor

A blown fuse or transistor is one good reason why your amp may not produce sound despite the power supply being intact.

You can easily identify a blown fuse or transistor from either visual inspection or smell. You can check for signs of melting or burning, and there is also the smell of something burning. In the event of a blown fuse or transistor, you will need to replace the damaged part with a compatible replacement.

Loosely Connected Wires

Another reason your amp is acting up can be poor wire connections. Wires connect the whole system, and sound frequencies are transmitted via these wires. If there is a break or loss of connection between wire joints, your amplifier will not produce sounds although the LED indicator is on.

Take time to trace the wires on the circuit carefully, and you can pull slightly to check for loose connections. If you find any breaks in the connection, you can use the soldering iron or solder to join them neatly.

Loose-Fitting Components

All the pieces on the circuit board work together to produce sounds from the amplifier, and if a piece is not well connected, it can prevent the amplifier from working properly.

If you don’t notice any blown fuses or parts and all the wires are well connected, the next step is to check for loose parts like capacitors and resistors. The capacitor andresistor are set on the circuit board, and there is a chance that they can come undone.

If one of these components is out of place, it will cause the entire circuit board to stop working, and hence no sound will be produced. Try to fix all the components properly and test the amplifier again.

Test the Resistor and Capacitor

Asides from the resistor and capacitor getting loose, there is also the chance that they might stop working.

We recommend that you test the integrity of these components, and you can do this with the multimeter. Set the multimeter to resistance and allow power to flow through the amplifier. The multimeter should read around 5%. If it reads lower than or way above 5%, there is a problem with your resistor, and if it doesn’t read anything, it means the resistor is dead.

You can also use the multimeter to test if the current is flowing through the capacitor, and if not, you will need to replace it.

You will need your soldering iron to remove or reattach a resistor or capacitor from the circuit board.

Test the Transformer

Another important component of the amplifier is the output transformer. The output transformer is responsible for producing a higher sound frequency and is the amplifier’s major unit.

You will need a screwdriver to open the transformer housing and expose the wires that transmit current. Once you’ve exposed the primary wires, test them with your meter, and check if the reading is consistent with the user manual.

An erratic reading indicates a faulty but functioning transformer, while no reading signifies a dead transformer. Depending on the state, you can repair or replace the transformer, but it is better to replace the unit.

Other Car Amp Problems

Repairing Car Amplifier

We have prepared some common signs that people observe when it comes to car amplifiers, and we want to tackle some of them.

Protect Mode Indicator

Some amplifiers are designed with a safeguard that stops them from working when there is an issue. This safeguard is also known as the amplifier protect mode, and a light indicates it.

If you notice your “amp protect light,” it means there is a problem with some of the components of your sound system, and your amplifier won’t work to prevent further damage.

You can test each component of your car’s sound system, from the head unit to each speaker, for any signs of damage.

Clipping Sounds from the Amplifier

When people complain of a clipping sound from their speakers, the fault is usually with the amplifier.

If an amplifier doesn’t have a compatible power rating with the speaker, it can cause that clipping sound. Also, faulty wires are another cause of clipping sounds in car amplifiers.

Hissing or Distortions

The cables that connect your car’s sound system are susceptible to external interference. Another common problem is a hissing noise or static from the speakers. In most cases, the hissing noise is not a result of faulty components but poor wire placement.

If you’re hearing hissing sounds, there is a good chance the cables are in contact with other power cables, and this causes negative feedback in your speakers. You can easily trace this problem by tracing the cables for your sound system and isolating them from other power cables.

If the wires are no longer in contact with other cables and the problem persists, you should check other components such as the speaker or subwoofers and the amplifier.

Farting Sounds from the Subwoofer

Three things can cause your subwoofer to make farting noises: poor mounting, impedance-matching, and poorly powered amp.

If your subs are poorly mounted, or the enclosure is poor, there is a good chance they will produce farting sounds. Adjust your woofers to sit properly, and ensure they are well fitted and enclosed.

Another thing to note is the impedance-matching, which is all about the sub and amp connection. A single sub or multiple subs can be connected to an amplifier, and you need to get the connection right.

An underpowered or overpowered amp can also cause farting noises from the sub. Get an amp with a compatible power rating as the sub next time.


The amplifier is an important part of our vehicle’s sound system, and any problem will cause poor sound production. Different components make up the amplifier, such as the input unit, resistor, transformer, ground wires, remote wires, and power amp.

Any of these parts can be the source of the problem, and we’ve shown you how you can identify them.

We’ve looked at how to repair a car amplifier with no sound and the possible causes. We’ve also looked at some of the tools you’ll need to repair your amp. There is more tolearn about your sound needs and other amplifier questions, so be sure to check out our other articles.