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Can Speakers Drain Car Battery?

If you enjoy blasting music through your car speakers in a traffic jam, I feel you. You turn your engine off, turn the music up, and wait for the traffic to clear up. But can speakers drain the car battery? Let’s find out.

Generally, speakers drain the car battery if the engine is off or the wiring isn’t done correctly. When the engine isn’t on, the alternator won’t generate electricity to power the car battery. In addition, any faulty wiring causes a parasitic draw that drains the car battery even if the speakers aren’t on.

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Tip: Having a flat battery after listening to the music can be really annoying. There is a way to avoid it when listening to your car radio at home without turning the engine on. 

You can simply connect your battery to the battery charger and plug it 

to the wall socket, that is it.

Different chargers may be required depending on the battery type you use, especially for lithium batteries, where you cannot use a standard charger.

I recommend charges below that I have been using for a long time, and I am happy with the way they work:

SUHU Car Battery Charger for standard acid and gell batteries

NOCO Boost HD GB70 2000 Amp for Lithium-Ion batteries

In the article below, I will go through several reasons why car speakers may drain car batteries and how to avoid this.

How Do Car Speakers Drain the Car Battery?

Car speakers drain the car battery when you listen to music with the engine off, the speakers are too powerful, or the wiring is bad.

You can stop this from happening by turning the engine on and driving around. Upgrading your car battery and redoing the wiring is also recommended.

In most cases, you just need to drive around a bit to recharge your battery, especially if you have stock speakers and the battery is good.

However, if you have replaced your car speakers, perhaps you or the person who did it for you didn’t connect the wires correctly. That makes the speakers draw power even when the car is off.

Or maybe the new speakers are just too powerful. For example, if you have replaced your tiny stock speakers with something like these powerful JBL GTO939 from the top Stadium Series, your old car battery just won’t cut it.

What’s more, these speakers are made from polyurethane, a highly resilient material that enhances sound while making your speakers long-lasting. 

Whatever the reason might be, here are a few solutions to your problem.

How to Stop Speakers From Draining Car Battery?

The best way to stop speakers from draining your car battery is by checking for a parasitic draw, replace the battery, redo or upgrade the wiring, and check the fuses.

Don’t worry because checking all these potential problems is pretty straightforward. 

Moreover, the solutions are pretty cheap, and you can do most of them yourself with a few household tools. So, let’s get started!

Parasitic Draw

Your car battery powers your radio, A/C, spark plugs, headlights, diodes, and pretty much everything else in the car.

If the car battery is dead, you can’t turn your car on, making you late for work or an appointment.

To check for a parasitic draw, you will need a multimeter. If you don’t have one, I recommend using AstroAI TRMS6000, which is a cheap yet effective piece of equipment that everybody should have in their house and car.

You don’t need to be an electrician or mechanic to check for a parasitic draw. Here is how to do it yourself:

Before starting any electrical tasks in the car, make sure that everything is off, especially the engine.

  • Pop your hood and locate the car battery.
  • Disconnect the negative cable (marked with a (−)).
  • Connect the red probe from the multimeter to the disconnected negative cable and the black cable to the negative battery terminal.
  • Wait for a few minutes and read the multimeter. 
  • A typical power draw is between 50 and 100 mAh (milliampere-hour). If it’s even less, that’s great, but if it’s higher, you have a parasitic draw.

In case you need a more in-depth explanation, watch this short video by EricTheCarGuy:

If you have a parasitic draw, it’s most likely the fuses or bad wiring. If not, then the battery is weak, and a replacement is due.

Car Fuses

Just like your house, your car has a fuse box. Fuses protect the electronic components from shorts and overloading, but they can also cause problems.

Replacing a blown fuse is easy and super cheap. Your car might have one or multiple fuse boxes. Here are some of the common places where you can find a fuse box:

  • In the trunk.
  • Under the driver or passenger’s dashboard.
  • Under the hood.
  • Below a car seat.

If you still can’t find the fuse box in your specific car model, do a quick online search or check the owner’s manual.

Once you have found the fuse box, checking the fuses is very easy. First, pull the fuse out and hold it against a light. 

If the metal wire inside is broken or damaged, replace the fuse with a new one. Of course, the replacement fuse must be identical (fuses are color-coded for this reason).

You can get the CrocSee 250 Pieces Car Fuses Assortment Kit from to get all the fuses you might need. This wide range of fuses is color-coded based on amperage (from 2A to 40A) to make them easily identifiable. 

replacing car fuses

Bad Wiring

Bad wiring is the most common reason for parasitic draws after installing aftermarket speakers. However, even if the wiring is done correctly, the stock wires might be too weak to power your new sound system.

Your new speakers might come with instructions on how to connect them. But wiring new speakers is challenging if you don’t have the expertise, so I recommend going to a mechanic for this issue.

Bad or Weak Battery

Last but not least, an old battery that isn’t powerful enough can cause many issues. Here are a few of the most common problems that occur when the battery needs replacing:

  • The car cranks a lot when starting the engine.
  • The car won’t start.
  • Headlights are blinking or aren’t bright enough.
  • The battery dashboard light is on.
  • The battery looks corroded and smells terrible.

Of course, replacing your car battery will stop the speakers from draining it when the car is parked. It will also help with other electrical issues that you might have.

If you haven’t replaced a car battery before, you can do it at home or take it to the service that will replace the battery for you in no time.

Remember to get a specific battery for your car model because putting in the wrong battery or misconnecting it is a fire hazard.

Excellent car batteries that are also able to support powerful car audio systems are Optima Yellow. If you are looking for one, check this wide selection on Amazon. 

Final Thoughts

When working at full capacity, your battery can power your speakers only for a few hours. If you listen to music with the engine off, the battery will lose power fast, especially with a powerful aftermarket sound system.

Keep your engine running to prevent this from happening. But if the car speakers are off and the battery gets drained overnight, you have a parasitic draw or an old battery.

Fixing this issue isn’t very expensive, especially if you have the technical know-how to do it yourself.