Fixed: Subwoofer Not Working But Amp Has Power

Subwoofers are excellent gadgets to amplify the sound quality of your audio system, whether in your car or home theater. But if your subwoofer stops working but the amp has power, there’s no need to replace it just yet. 

In this guide, we’ll explain all the troubleshooting steps to fix this issue:

What to Do First: Basic Troubleshooting

If you have turned ON all the pertinent devices, but the subwoofer fails to function, it might be best to check other components of your setup. 

If there are no sounds coming out from the subwoofer, it is best to do initial troubleshooting by following these steps: 

Polk DSWPRO 550wi Wireless-ready Powered Subwoofer

For a comprehensive but easy approach, continue to the next section of this article. 

How to Fix a Subwoofer That’s Not Working Even If the Amplifier Has Power

If you have little to no experience when it comes to troubleshooting your subwoofer and any of the devices from your setup, then it might be time to seek professional help. 

But if you want to try and fix it yourself, here are easy steps to help you fix your subwoofer.

Step #1: Check all the Control Knobs

Some users tend to forget to check the volume knobs for the amp and the subwoofer, gain, and bass knob. Closely inspect these knobs once you have them powered up.

subwoofer knobs

If the volume level is low, just turn the volume control up. This can be the reason why there is no sound coming out from the device.

Also, check the gain knob of the subwoofer and blast them to the highest to gauge the output levels. The gain knob is responsible for the volume that comes into the channel. 

Lastly, closely inspect the bass knob and make the right adjustments.

Step #2: Check the Input Cables

When you find that the amp is working properly and the subwoofer does not produce any sound, check the input cables. Any cable issue will lead to transmission loss and result in audio issues. 

Check and ensure that the input cables are properly plugged in and fix any loose cable. You can also remove the RCA cables from the head unit and inspect them for breakage, cuts, or any open sections. Additionally, you might want to check the Y adapter cables for any damage. 

checking subwoofer input cables

Connect it back once you see no damage. Once properly connected, switch the unit ON once the input cable is connected. If no sound is produced from the subwoofer, change the cables.  

Step #3: Check the Wires

There are two wires connected to the subwoofer, and these include the power wire and the speaker wires. Check these wirings. 

Faulty wiring or a wiring issue can lead to an unresponsive subwoofer despite properly powered amps.

Step #4: Check the Subwoofer Fuse

The subwoofer fuse is an integral component to power up your sub. The fuser can get busted whenever a power surge occurs. 

The fuse blows with the surge, resulting in a short circuit where electricity cannot flow. Locate the fuse using the user manual and immediately replace it once you detect that the fuse wire has been blown off.

Step #5: Check the Speakers Closely

A failing speaker wire is also a common issue when the subwoofer overheats. The speakers can also be the cause of the unresponsive subwoofer. 

subwoofer speaker

Replace your speakers if you suspect that they are already damaged. Make sure to purchase speakers with similar specifications to your current one to match the requirements of your home receiver.

Step #6: Check the Subwoofer’s Settings

Ensure that the subwoofer is not muted and the volume is not too low. It might be possible that these setting-related issues can resolve the problem.

Go through the other settings of your model, and see to it that the amplifier-subwoofer settings are in proper order. 

Step #7: Ensure that the Subwoofer and Amp are Grounded (For Car Subs)

Also, check the ground for both the subwoofer and the amp. This can be done by disconnecting the battery’s ground terminal, setting the multimeter to Ω setting, and touching the test leads to check resistance. 

car amp with speaker

Proceed to subtract the obtained readings from further measurements for better accuracy. Lack of ground can lead to a hissing or humming sound and damage both devices.

Step #8: Check the Voltage Requirements of the Subwoofer and Amplifier

Check the required operating voltage of your amplifier [1]. Make sure that enough power is flowing to the amplifier. Many amps power on 6-10 volts but would require at least 12 to 14 volts.

Troubleshooting Tips and Tricks

Here are additional steps to help you resolve issues concerning a subwoofer that’s not working when the amp has power. 

1. Inspect the speaker’s levels and settings to enable the subwoofer. This may vary depending on each model, but here are the steps in general: On Settings, select Speaker. Choose Speaker SP from the options, then check and monitor the speaker pattern.

If you see the pattern ending with a 1 or 2, it means that it’s resolved. However, if the pattern closes at 0, you must take further steps to fix the issue. 

Audioengine S8 Wireless Subwoofer

2. Check if the subwoofer’s power cord is tightly plugged into a working AC outlet. 

3. Tune the frequency level to its highest. This way, the subwoofer will absorb all the low-frequency signals.

4. Lastly, check if your subwoofer has a standby mode setting. This might be the reason why your subwoofer is not working. If so, check the subwoofer’s manual to disable the standby setting.

What if the Subwoofer Turns On But Has No Sound?

How To Buy The Right Subwoofer


Check the subwoofer’s compatibility with your space and if it contains ample air volume. There are also readily available specification sheets that you can check to see if it’s the perfect fit for your intended mounting area.

Sony SACS9 10-Inch Active Subwoofer

Voice Coils

The subwoofer’s voice coils can either be single or double. We highly recommend a sub with a single voice coil if you want a simpler setup. A dual setup gives you more options and flexibility in setting up multiple subwoofers and amplifiers. 


Check the RMS continuous power rating as well and see if it matches your amplifier’s. If you want a sub with no external power source, you can opt for an active subwoofer. This type has an amp built-in, unlike a passive model.

Vented or Sealed Box

Calculate the Efficiency Bandwith Product (EBP) to determine whether the subwoofer requires a vented or a sealed box.


How do I know if my sub amp is blown? 

You will know if your sub amp is blown by checking the fuse. You can utilize a multimeter to inspect the circuit between the fuse. 

How long does a subwoofer last? 

A subwoofer can last for a long time. These units can last for decades with proper care and maintenance.

How much will it cost to install a sub in a car? 

It costs around $100 to install a sub in a car. This is the normal cost of installation, but it still depends on the number of subs you want to be installed.

How much is a subwoofer?

A subwoofer generally costs between 100 to 200 USD. 


A subwoofer and amplifier combo adds more power and bass your the audio system. However, connection issues between the two devices may arise. We hope these troubleshooting and accompanying tips mentioned in this article can help you with your subwoofer issues. 


Picture of Willie Greer
Willie Greer
Willie Greer is the founder of The Product Analyst. A cinephile, he has made it a personal quest to achieve the awesomest home theater possible. He now shares what he has learned through the years on the site, and has enlisted the help of tech-savvy colleagues in providing more insight about today’s most sought-after gadgets.