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How Long Before Car Battery Dies With Radio On: Top 4 OMGs!

Last Updated on: April 9, 2024

The stereo is the most crucial vehicle component that we all love and use whenever driving. It makes the ride lively by providing the needed entertainment when you hit the road. But have you ever wondered how long does a car battery last with the radio on, especially when the engine is not running? 


You’re not alone; most folks have ended up with a flat battery after leaving the radio on while the car isn’t running. So if you want to know how long before car battery dies with radio on, please read on…

Does Leaving Your Car Stereo on Drain the Battery

When a vehicle’s head unit, receiver, radio, or stereo drains the car battery, it is a parasitic draw. The term parasitic draw refers to your car’s electrical components consuming electricity when they shouldn’t, which in this case is when the component is not being used or when the car is switched off. 

Your car radio is among the different components that can leave you with a dead battery through a parasitic draw. In most cases, a parasitic draw can happen without your knowledge, and at times it can happen really fast. Some of the signs of parasitic car battery drain include:

  • The dashboard battery light turns on.
  • Car struggles to turn on
  • Some components remain on, even when the car is turned on
  • Excessive engine cranking

Generally, leaving your stereo on can drain your car’s battery, but this depends on a wide range of factors. For example, the car radio doesn’t need a lot of power to function; therefore, you can’t accuse it of draining your battery. But it’s different if you leave the radio on for several hours with the car not running.

When you turn your radio on, you switch on the car’s entire electricity system. Plus, if your car’s interior light or headlights turn on when you insert the key in the ignition, the lights can also play a role in draining the car batteries. Another cause of the problem that most car owners dismiss is battery failure. 

Generally, the battery power of most cars is 60AH, which means that they can supply 6Amps for about 10 hours or 60Amos for 60 minutes. 

Your car’s stereo only needs 5 amps, but if you want to increase the volume, you’ll need more power. In this case, your battery will last for a few hours before it drains. Remember, the starter motor requires about 130 Amps to start your engine; therefore, you might not be able to start the car in a few hours if you leave the car stereo on and don’t have jumper cables or a battery charger.

How Long Does the Car Battery Last With the Radio On?

Generally, a radio draining car battery when it’s off can take a few hours, especially since it is the main component consuming electricity. Therefore, leaving your radio running when the engine is off can drain the vehicle battery. But they don’t use too much energy, so the problem may be caused by other components like the lights, heater or fans.

Another factor you must consider is that the amount of energy needed to play a radio will depend on your car’s audio system. For example, if you have energy-consuming car speakers, then your battery will drain faster. Plus, some radio systems have a large screen that can drain a lot of energy.

Meddling around with the switches can likewise drain your battery faster. So how long does a car battery last with the radio off will depend? 

If your car’s battery is in great shape, then you can let it play for hours with little to no issues, but make sure your AC and lights are off.

Watch This!

Fun Fact: If your car radio appears to be draining your battery, then don’t you think it is high time to add another battery to your car? Know the signs of when to add a second battery for car audio so that you won’t be bothered by a dying battery on your next road trip!

Why Is My Car Radio Draining the Battery?

The main reason why your car’s radio needs the battery is to function, but this is not always the case. When the car is running, the battery doesn’t power the radio; instead, it’s powered by the alternator. The battery does not have too much to do when the car is running since the alternator is powering all the car’s electrical components.

The main reasons why the battery dies include poorly connected radio, bad fuse, or wiring problems.

Other than these factors, the car’s battery may lose its capacity to power the car’s electrical components. The battery will fade away when this happens; making it seem like the radio is the problem. 

Some of the leading causes of radio draining a car battery when off include:

1. Bad Radio Fuse

Bad Radio Fuse
Bad Radio Fuse

A huge percentage of the aftermarket stereos come with a faulty fuse that wears out or breaks faster, resulting in surprising battery drains. The fuse is normally situated in the fuse box, and it can function as a switch fuse (which works when the vehicle is on) or a constant fuse (which is always powered). Worn-out fuses can cause lots of issues with time, and they can drain the battery when the vehicle is off.

A constant fuse is rarely the cause of the issue; after all, the battery can be drained by a fuse that isn’t installed correctly. 

An incorrectly installed fuse can also cause unwanted battery drains; therefore, you may have to install the fuse correctly.

2. Old Model Radio 

Old Car Radio
Old Car Radio

When the radio gets old, some of its internal components, wires, and fuses wear out; therefore, the battery will be drained sooner rather than later. You can salvage the radio by replacing the worn-out parts, but the best solution is to replace the radio.

3. Poorly Connected Radio

Poorly Connected Radio
Poorly Connected Radio

If you recently installed a radio and it functions properly, but then you notice that your battery is draining quickly. If the battery problem starts immediately after you have installed the radio, then the installation process may be the issue. You may have made a simple mistake while installing the radio.

4. Overpowered Stereo

Overpowered radio
Overpowered Radio: Manga Version

If you’ve installed a new stereo and it starts draining your battery, even if the installation is perfect, you have purchased an overpowered stereo. This happens when you are using subwoofers or potent speakers. Rugged systems use more energy; therefore, you shouldn’t be surprised when your battery dies.

Fun Fact: It is easy for car owners to jump to conclusions about stereos draining the car battery. There are other types of equipment in your car that might be contributing to battery drain. Poor grounding could be one of them! Research on symptoms of a bad ground car audio and proceed from there.

Listening to the Radio Without Draining the Car Battery

The best way to listen to the radio without the risk of draining your car’s battery is to use a portable one. If you’re worried about the battery running out, you should get a pocket radio.

A huge percentage of vehicles use their FM radio to produce a film sound, but nobody wants their battery to run out. Therefore a portable speaker or radio can come in handy. But, regular maintenance of the battery cables and the battery itself can improve the battery life of your older car. 

Frequently Asked Questions

How to Listen to the Radio Without Draining the Car Battery?

The duration of the stereo use will depend on a number of factors, but if it’s new, then the battery life can exceed 3 hours with the radio on and still start the vehicle afterward. But if the battery is in good condition and the battery terminals are ok, then you should start the car at intervals.

This way, your battery will charge up, but it’s always a good idea to carry a portable radio. This will save you time and prevent the battery from wearing out. 

Can ACC Mode Drain the Car Battery?

No, the ACC mode won’t drain the battery. The ACC is an exceptional car mode that does not use up the charge. But if you are using several components while in this mode, then you may end up draining the battery, especially if you forget to charge it for a very long time.

How Long Can a New Car With a New Battery Last With the Radio On?

If your vehicle is new, then the new car battery can last for between 4 to 6 hours with the radio on. But if you have upgraded the system with speakers, subwoofers, or amplifiers, then your battery may drain faster.

Note: A subwoofer can reduce the life of a good battery by about an hour.


Radio drain car battery is a common problem that has left many car owners with little to no power to start their car. This problem can drain a fully charged battery within the shortest time possible. No one loves carrying jumper cables, even when going for short trips. Therefore, if your car always has a drained battery, you should have the car charging system, audio system, and battery serviced.

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