How Long Before the Car Battery Dies With the Radio On? [EXPLAINED]

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How long can I run my car’s stereo system before I drain the battery?

Given that your car radio is the only one consuming power, it should take about 8 hours for it to deplete your battery if you are using a standard car battery. However, the battery is likely to drain faster or in two hours less if your car has a sub and amp.

A common question that many car owners have is how long before the car battery dies with the radio on. Most car batteries can run the radio for several hours. It would, however, be dependent on the battery, the radio, and the number of hours you use it.

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Here, I will walk you through some important things related to the topic that you should be aware of, as well as explain how to listen to the car radio without draining the battery.

The calculation

Here’s a high-level overview of the batteries on your car. The majority of them have a capacity of 60AH. That is, they can provide 60 amperes for one hour or 12 amps for five hours. A standard stereo will need about five amperes of power. It will most likely not suffice when it comes to increasing the sound. Therefore, having your radio on will typically give you a minimum of three to fours hours until the battery drains.

Can Car Radio Drain My Battery?

In general, the car battery will be down within a minimum of three to three hours when the radio is left on. Regardless, it is not ideal to have your radio on while your vehicle is not running. Not only will it drain your battery, but it will also lead to problems that surface when you try to start the engine.

The length of time you can listen to the radio using only a car battery is determined by two factors: the electric draw of your radio and the strength of your battery. Because the car battery is displayed in ampere-hours, considering the current draw in amperes of radio makes determining the maximum listening time simple.b

Without amps, older vehicle radios would usually draw between 0.25 amps and 1.5 amps. With a car battery strength of around 40Ah, it should last for several hours at a conversational level of volume.

Modern car radio systems, on the other hand, have amps and can draw 1.6 amps or more even when turned off and the volume is at zero.

And with the volume turned all the way up, it can draw more than 10 amps. Modern devices will draw around 5 amperes of current at some standard volume levels. With a 40-amp-hour battery, the highest listening time before the battery completely drains is between 4 and 8 hours.

If your car has an aftermarket sound system with an amp and sub, the draw of the current can easily reach 25 amps, reducing the amount of time it can operate on the car battery.

Can the Car Battery Affect the Car Radio?

When you switch off the engine, all of that power is no longer required, so all of the accessories are also turned off. They do not utilize any power once they’re all turned off. However, if you leave your car radio on after switching off the engine, it will continue using power since it is drawing from your battery.

If your battery is in poor condition, the radio may begin to malfunction if you leave it on for an extended period.

Internal fuses in the radio can blow out if they get too close to the end of their useful life, and they will stop functioning until they are changed or a new battery is installed.

How to Listen To Radio without Draining Car Battery

You can listen to the radio for two to three hours on average without draining the battery of your car. You can leave your car in an accessory mode for half an hour to forty-five minutes. The latest cars, however, turn off the accessory mode after twenty minutes to avoid depleting the battery; this is either on a timer or the car evaluates how much electricity is utilized.

Hey, there mobile audio lovers! My name is Vincent Talbot, founder and chief editor at 99carstereo.com. Ask any mobile audio fanatic, installer, or company rep what makes a good car speaker, sub or amp, or, better yet, why he or she prefers a certain brand over another, and be prepared to endure a litany of opinions, viewpoints, and passion-fueled perspectives. To be honest, mobile audio shopping can be a daunting task without a guide, so I’ve assembled what I feel are the best products to consider to make things easier for you. More about me.

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Mobile audio is my passion, so before I put anything in front of you I exhaustively research a broad range of products, review all the available information on them and ultimately make a curated list of recommendations. As a result, I want this site to be a trusted resource that you can rely on and that is not rigged by brand sponsorship, so you can use this information when you are planning your new mobile audio upgrade.