Car Amp Turns on But No Sound From Subs [SOLVED]

Have you ever had your car amp turn on and subs are not making any sound? If so, then we want to help you out. There are a number of things that could be going wrong with your system and we’re going to discuss them below.

car amp turns on but no sound from subs

The first thing is checking the connections from the amplifier to each subwoofer. This includes looking for loose cables, corroded terminals, or broken wires. You should also check if all of your speakers are connected properly by using an ohmmeter or continuity tester. The last thing is checking the fuses in both the car and amplifier as well as any wiring between them.

To let you understand things better, here are detailed explanations as to what and how you should check to fix the car audio system-

How to Fix a Subwoofer with No Sound?

As we have already hinted above, there can be multiple reasons behind a subwoofer not producing any sound while Amplifier is turned on. Here are those-

Settings Issue in your Stereo

If you’re not getting any sound from your subwoofer, the first thing you should check is the settings on your stereo. Make sure that the bass or low-frequency output is turned up high enough to hear something.

Also, some people like to turn down the bass when they’re driving so it’s not as jarring. So make sure that’s not the issue.

This is applicable especially to cars with aftermarket car stereo systems as those have many customizable subwoofer settings for better sound quality, some capable of completely shutting down the subs leading to no sound from them.

That’s why we recommend carefully checking all the settings relating to the subs in the head unit so that you are 100% sure that the problem is elsewhere, not in a setting that you could have solved in a few minutes.

Amplifier Not Getting Enough Voltage

If your car amplifier is not getting enough voltage, it will not be able to amplify or produce sound to the extent when the subs get engaged. The reason for this can be a bad alternator, a problem with power wires or a fuse, or even a low battery.

You should start by checking the voltage at the amp and making sure that it’s above 11 volts. If it is showing less than 11 volts, then you’ll need to troubleshoot the battery connections and see if there is an issue. If it’s not, then you’ll need to take a look at the battery and replace it if necessary.

In most cases, it’s as simple as a loose power cable causing low voltage input. If it’s the case, connecting the cable properly should solve your issue.

However, if the cable is perfectly connected, you should check the positive and negative terminals of the car battery for any corrosion or loose connection. If they are loose, tighten them up. Clean the terminals, in case they are corroded.

However, if you find that the battery is perfectly fine with enough charge and the cables are perfectly connected, yet the voltage is not enough. Then there is a great chance that the power wire is damaged somewhere in between the amp and the battery. Replacing that cable with a new one should fix your issue.

System Overheating

One of the reasons your car amp might not be producing any sound could be that it’s overheating. When an amplifier gets too hot, it will automatically shut down to protect from any damage.

There are a few things you can do to help prevent this from happening. First, make sure there is enough airflow around the amplifier. If you don’t have the space to install the amplifier without it getting too hot, you can purchase a heat sink and install that on top of the amp.

Another thing you could do is turn on the air conditioner to cool down the car interior which should help the amp to settle down quickly. Once the car amplifier cools down, it should provide the desired sound you were looking for.

how to fix subwoofer with no sound when amp is okay

Input or Output Cable is Loose or Damaged

The next things you should check are the cables and wiring between your amplifier and subwoofer. This is often a common problem as overtime, wires can become corroded or loose. You can test this by gently wiggling the amp input and output cables to see if there’s any noise coming from the subwoofer.

Another issue could be the RCA cables that carry sound signals from the CD player to the stereos. Whether you have bad RCA cables or RCA cables that have a poor connection, the outcome will be the same, no sound coming from subs. You can test those by simply disconnecting them from the stereo and then connecting mobile or laptop to it.

Plus, if the machines are wired incorrectly, you’ll have a hard time sorting things out.

If you don’t hear anything after connecting an external device and playing music tracks in them, there is a good chance that either the cable is damaged or the input jack is faulty.

However, if everything looks fine and you are still getting no sound from the subwoofer, then it’s most likely that your amplifier has other issues. So, proceed to the next step.

Poor Grounding of the Audio System

One of the most common problems with audio systems is poor grounding. This can cause all sorts of issues, including no sound from car subwoofers.

There are a few things you can do to help improve the ground connection on your system:

  • Use a proper grounding cable without any damage to it.
  • Make sure to connect the ground wire to the right input slot.
  • Ensure proper ground by connecting the cable to a bare metal surface in the car.

The subwoofer is Turned off Through Remote

Some stereo systems come with a remote control that allows you to adjust a whole lot of settings without messing around the dash. This could include turning the subwoofer on or off.

If you’re certain that the subwoofer is turned off through the remote, then all you have to do is press the button to turn it back on.

On many occasions, we have seen people scratching their heads finding the problem as they see amp’s input and output, electrical signal, RCA wires, all are properly connected.

But nothing is happening and ultimately figures out that there was nothing wrong with the power system, grounding bolt, or any other thing. That was just a remote setting that turned off the subs.

Incompatible Subwoofer

If you have just installed a new subwoofer on your car stereo system, you should make sure that the new subwoofer is compatible with your old stereo.

Some stereos can only handle certain types of speakers and sometimes it’s not possible to update them anymore. If this is the case for your car amp, then there are a few options available:

You could try buying an external controller that would allow you to use any subwoofer with your stereo.

Another option is to purchase a new stereo system that is compatible with the type of subwoofer you have.

The last resort would be to sell the incompatible subs and bring in a compatible pair.

Amplifier is on Protect Mode

If your amplifier is on protect mode, it’s usually because there is something wrong with the system. This can be caused by a number of things, such as:

  • Overheating
  • Short circuit
  • Input overload
  • Output overload
  • Speaker failure

In most amps, there is a light indicator that hints you whether it’s in protect mode or not. If you find that the amp is in protect mode, the first thing you need to focus on is the amp as there is a great chance that the protect mode on the amp is what restricts the subs from producing sound normally.

Bad Fuse or Blown Fuse

The last thing you can check is the fuse. If the fuse is blown out, the system should get no power at all. However, sometimes people use the wrong fuse that causes a wide range of problems in the car.

If you have recently replaced the fuse, it can be a wrong fuse that’s preventing enough power to pass through. Swapping that with a perfect one should solve the issue here.

Faulty or Bad Subwoofer

The last possibility, and unfortunately the most expensive one, is that the subwoofer itself is faulty. This can be caused by a number of things:

  • Damaged cone
  • Bad speaker wiring
  • Defective crossover

If you have ruled out all other possibilities and it seems like the subwoofer is at fault, then it might be best to purchase a new one that’s compatible with the overall car audio system.

Faulty Amplifier

If the amplifier is faulty, it means that you will have to get a new one. However, there are ways to prevent this from happening in the first place!

The best way to do this would be to purchase an amp with an adjustable gain switch on it. This allows you to adjust the input signal of your amplifier according to what type of speaker you have installed, thus stopping it from being damaged.

There are a few other precautions you can take to prevent your amp from being faulty in the future too!

Make sure that there is enough ventilation for all the amps parts. Make sure not to place any heavy objects on top of an amplifier and install it so it cannot get exposed directly to the sun.

Although you can fix car amp, on most occasions, they don’t last long.


If you’re not getting any sound from your car subwoofer, it could be for a number of reasons. The first thing to do is make sure that the bass knob or remote control isn’t turned off on the amp itself.

If there’s no change in volume, then it may be time to check input-output connectivity, power and ground wires, other cables carrying electrical signals. And ensure proper grounding by connecting the cable directly to bare metal surfaces in the car.

You can also try switching out speakers or replacing fuses before buying new subs altogether. We hope this article has helped you troubleshoot the no sound from subs issue.

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