Why does my Car Subwoofer Turn On and Off?

Why does my Car Subwoofer Turn On and Off?
Why does my Car Subwoofer Turn On and Off?

Subwoofers are an important part of our cars, as we have become habitual to them. Sometimes, we observe that our car subwoofer stops working or keeps on turning on and off by itself. There can be many reasons for this.

Why does my Car Subwoofer Turn On and Off? Your car subwoofer can turn on and off, again and again, because of the amplifier going into the protection mode, loose wiring problems, insufficient sources of power, damages in the amplifier, defective wire leads, poor fuse, overheating of the amplifier, and damage to the cone seal.

We have also added the best methods to fix car subwoofers from turning on and off.

Why does my Car Subwoofer Turn On and Off?

In this article, we have added 8 main reasons that cause a car subwoofer to turn on and off. We have explained all these reasons in detail here:

Amplifier in Protection Mode

Sometimes, the amplifier of a car subwoofer may undergo a protection mode. The amplifiers of some car subwoofers have LEDs on them that light up in this mode. Some amplifiers also have different LEDs that show different kinds of fault through colored lights.

The main reasons behind the amplifier going into this protection mode include overheating, internal failing, improper installation, and loose wires. Due to these problems, the car amplifier keeps ongoing and returning from the protect mode, which causes the subwoofer to turn on and off again and again.

So, whenever you observe a light popping up on your amplifier, it indicates protection mode. In this situation, you only have to identify the problem that led it to this mode to recover it.

First of all, you must ensure that all the onboard fuses of the subwoofer are plugged correctly into the amplifier. Also look for blown fuses, if any. If the fuses are connected properly, there may be an issue with the ground wires.

The ground wires may be defected or improperly connected to the subwoofer. If the ground wires are also installed properly, the problem is probably due to overheating. In this situation, you should turn off the subwoofer for some time, until it cools down.

Loose Wiring of the subwoofer can make it turn on and off

The coming reason behind a car subwoofer turning on and off by itself is loose wiring. If you observe that your amplifier is not in the protection settings, you must check the wiring of the subwoofer.

When the turn-on wire of the amplifier of the subwoofer is connected to the remote antenna of the head unit, instead of the remote-wire, it may cause the subwoofer to turn on and off whenever the input is changed.

Besides, the lead wires of the subwoofer may also be loose, causing it to turn on and off. Wiring is one of the main problems that cause a subwoofer to work improperly. In this situation, you have to observe all the wires connected to the subwoofer and identify the one (or more) that is loose or defective.

To detect a loose wire, a 9-bolt battery can be used. Firstly, you should connect the battery to the car subwoofer’s leads, by connecting positive ends with the positive side of the wire, and the same for the negative ends. In this condition, if the car subwoofer shows pulses, it means that its internal wires are loose.

To fix the loose wires, you should remove the dust cap of the car subwoofer. You will see all the wires of the subwoofer connected to their respective terminals. If you see any of the wires loose, fix it by using a spanner or by hand. Loose wires may be caused by over-using the subwoofer. You should keep a check on the subwoofer wires regularly to avoid such problems.

Insufficient Power

Another reason for car subwoofer turning on and off instantly is a problem in the power sources. The main reasons behind insufficient power reaching the car subwoofer include wiring issues, a problem with the ground connection, blown fuse, loose connector, or a faulty head unit. This can result in bad or no sound coming from your car stereo system.

When the sufficient power is not reaching the subwoofer, or it reaches in irregular intervals, the car subwoofer turns on and off by itself irregularly. In this situation, it is necessary to identify the main issue behind the power shortage.

To check the cause of insufficient power, first of all, check the fuse of the subwoofer with the help of a multimeter. Turn off the power of the whole system and then set the multimeter to ohms. Next, touch the testing leads of the multimeter with the fuse’s metal caps. If reading is recorded, it means that the fuse is working properly.

If the fuse of the subwoofer is working properly, there may be an issue with the head unit. The head unit may not be receiving the required power, i.e. 12V. By using a voltmeter, check the power reaching the head unit. If the power is insufficient, check the wires connected to the subwoofer as described before.

Faulty Amplifier

An amplifier is an important component of a car subwoofer, and if the amplifier becomes damaged, the subwoofer may start turning on and off by itself. The main reasons behind an amplifier becoming damaged include insufficient power, faulty wires, etc. Class D amplifiers are good and delivers awesome sound quality.

The amplifier may itself be blown up completely, which causes the subwoofer to turn on and off irregularly. In this situation, it is necessary to find the main issue with the amplifier to get a perfect solution.

If you observe that there is no issue with the wiring or power supply of the amplifier, you have to replace your amplifier with a new one. This is because the lifetime of the amplifier may have reached its limit.

Open the hood of the car and remove the current amplifier by disconnecting all the wires. It is better to purchase a new wiring kit for the new amplifier. Disconnect the battery of the subwoofer and connect the corresponding wires carefully with the new amplifier. Your car subwoofer will start working like a brand new subwoofer!

Defective Wire Leads

In some situations, the wire leads of the car subwoofer may be defective. This is because of insufficient power coming into the wire leads. Besides, the wire leads may also become defective due to high power reaching the terminals.

Defective wires cause the car subwoofer to turn on and off instantly. When leads become defective, it becomes difficult to locate the main issue. In this situation, it is necessary to replace the lead wires through some simple steps.

To replace your car subwoofer’s lead wires, first of all, heat the dust cap of the subwoofer to loosen the glue on it. Next, disconnect the lead wires of the subwoofer from the VC wire.

Use a flexible solder and wire that are suitable for the VC wire of the subwoofer. It would be beneficial if you epoxy the wire to the cone. Next, connect the terminals of the new lead wires correctly with the VC wire ends and glue the dust cap of the subwoofer back.

Poor Fuse can cause subwoofer to turn on and off

The car subwoofer may turn on and off due to a poor fuse. Usually, there are about three kinds of fuses in a car subwoofer. It becomes difficult to find out the faulty fuse in this situation.

The main reasons behind a fuse getting blown up include wiring problems, power supply issues, and the problems with the internal amplifier. In this situation, you just have to follow some simple steps.

First of all, you have to locate the faulty fuse of the subwoofer with the help of a voltmeter. Next, replace the faulty fuse with a new one. If the fuse blows again, there may be an issue of a short circuit.

In this situation, replace the fuse once again while keeping the amplifier disconnected. If the fuse blows once again, there may be an issue of wiring. After ensuring the mitigation of all such issues, use a new fuse for your car subwoofer.

Tip: To avoid fuses from getting blown, set a proper timing for using your car subwoofer. Avoid overusing the subwoofer to keep it safe and undamaged.

Heat Issues

When the amplifier of a car subwoofer is on, it produces heat continuously, which is why the installation of an amplifier in a restricted location having poor sources of ventilation can result in serious problems.

If the amplifier of the car subwoofer does not have a proper system of ventilation, the subwoofer may overheat, which can turn the amplifier into the safe mode. Overheating also produces irregular sounds from the subwoofer, causing it to turn on and off again and again.

In some situations, the overheated amplifier returns to its original state on its own after cooling down. However, overheating can sometimes result in permanent damage to the subwoofer.

Another reason behind the car subwoofer becoming overheated is the amplifier clipping the coils of the subwoofer. When the coils of the subwoofer become overheated, the subwoofer turns on and off again and again irregularly. It is a common issue of car subwoofers and can happen with everyone. Thus, you do not have to worry a lot about this problem.

The common solution to car subwoofer overheating is to leave the subwoofer off for some time and let it cool down. To fix the overheated subwoofer, locate its cooling fan. Check the blades of the fan and ensure that they are spinning properly.

If the blades are not spinning appropriately, the cooling fan may have defected. Check that the connector of the fan is connected with the socket properly. If the fan still does not work, there is a need to replace the fan.

Besides, you should also check the ventilation vents of the car subwoofer. Ensure that the ventilation vents are cleaned properly, and no dust is stuck in them. If you see any dust, remove it to facilitate the flow of hot air outside.

Lastly, you should also keep a check on the location of the amplifier of the subwoofer. You must ensure that the amplifier is connected to a well-ventilated place. In this way, overheating can be prevented easily.

Problem with Subwoofer Cone

A car subwoofer usually produces the sound having a frequency of about 20 hertz to around 200 hertz. The subwoofer contains a cone, which has a diameter of about 9 inches to about 20 inches. Any issue with the cone can cause it to turn on and off again and again.

To run a car subwoofer properly, air must be moved through it frequently. It is usually done by moving the cone from the back and front to facilitate the movement of air. The cone of the subwoofer is usually sealed to the insertion area by any one of multiple materials.

If the seal is damaged or broken, air cannot move properly through the subwoofer. In contrast, the air moves around the edges of the cone into the insertion area. In this situation, the resistance of the subwoofer also decreases, which causes the car subwoofer to turn on and off again and again.

If the cone of your car subwoofer is damaged badly, you must repair it on time before it damages the subwoofer completely. The crack can enlarge if you listen to music in high bass. If the cone of your car subwoofer is made up of plastic, you can fix it easily with the help of a goop glue

After repairing the seal of the car subwoofer, you must ensure that it is fixed properly. If the subwoofer still turns on and off, replace the cone of the subwoofer. It is the best solution to avoid any future problems with the cone seal.


To avoid these issues, the suggested steps must be followed. Besides, it is recommended that you should not overuse the car subwoofer and listen to music at a very high bass that may cause the subwoofer to blow out.

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