Can A Car Radio Drain Your Battery: Problem Fixed

can a car radio drain your battery

The car radio is a source of entertainment in our vehicles while we drive around town.

We get news updates and traffic information, and we listen to lots of music. Some radio systems can be used as GPS solutions to guide you wherever you want to go.

The issue right now is that your car radio needs some energy to function, including your car.

When you leave the vehicle lights on, it will surely drain your car battery. But what happens when your car radio is left on? Here’s what happens when you use your radio.

Does Car Radio Drain Battery?

Certainly, the car radio can drain your battery when it’s left on for several hours while the vehicle’s engine isn’t functional.

The radio drains your battery because your car’s electrical system turns on whenever your stereo or radio is running, which can elevate the parasitic draw on your car battery.

But you should know that car radios do not consume a lot of power when turned on. This also applies to recent car models with powerful speakers, amplifiers, and stereos.

It is most unlikely that putting on your radio will drain your battery when driving or when your car engine is turned on.

However, keeping your radio running for hours when your engine is shut down can gradually drain your car battery.

It might drain the battery at a slow rate, but it will eventually shut down your battery if you don’t intervene on time.

To avoid situations like this, you have to start practicing good habits. It would be best to only put on your car radio when your engine is running.

If you must enjoy your favorite music, you can bring a rechargeable portable Bluetooth speaker that doesn’t need the power of your car battery to function. Developing the right habits and being cautious of your energy consumption can help improve your car’s battery longevity. This will assist in preventing unfavorable situations or any car battery problems.

How Long Can a Car Battery Last While Playing Radio?

The period of time you can run your radio on your car battery when your engine isn’t running depends on your vehicle’s battery capacity.

Some car batteries can last up to eight hours while your radio is working.

The capacity of your battery and the kind of radio installed in your vehicle are the main factors that decide your battery’s longevity.

Recent car radios draw more power than older ones, so the battery of an old car might tend to last longer when the radio is turned on.

In some old vehicles, the battery capacity is rated at around 40Ah. This type of battery can last for many hours because old vehicles do not have a radio designed with amplifiers, subwoofers, and speakers.

Your radio can run for several hours at a low sound volume without consuming much of your battery power.

While you do this, your radio will consume just about 1 amp, which is so much less than the power usage when your radio is set at a very loud radio volume.

You can get a 60Ah battery capacity in modern vehicles, and this means that the battery will be able to deliver up to 6amps for about 10 hours.

While your car battery capacity is high, the stereos will have more power-consuming components. These stereos can take up to 1.6 amp or even higher, and this still happens while your stereo is idle or the volume is set at a low level.

Modern stereos can draw up to 5 amps when the volume is set at a moderate level. But when you’ve your stereos running at maximum volume, your device will take up more power.

Why Does My Car Radio Drain My Battery: How to Fix It?

Wiring System

When it’s a wiring system problem, the stereo installed in your vehicle will begin to drain a lot of power from the vehicle’s battery.

If you carried out the wiring yourself, there might be a chance that you did the wiring wrong at some point.

When the wiring isn’t done properly, it can cause your stereo to consume a lot of battery power.

A new stereo usually comes with an installation guide. You must install the stereo just as the manual stated to avoid any issues when you are done.

But sometimes, you might notice that the instructions are not detailed enough or well-explained, so you tend to make some mistakes.

Each car made has a fuse box, and in some conditions, they also are designed with fuse ports. Some of these fuse ports are stationary, and the other type is switched. Switched fuses are powered when you turn on your engine.

In contrast, the stationary fuse takes up energy even when your vehicle isn’t on.

So, connecting your stereo to a stationary fuse can cause your car radio to drain a high amount of battery energy.

You must remember that you should only connect your car stereo to stationary fuses.

How to Fix

How your fuse box is being installed differs with vehicles. Hence, you need to differentiate between a stationary and switched fuse, and to do that, you have to manually check the fuses.

You have to get a Kaiweets Voltage Tester. It is always available. When you have this tool, follow these steps:

  • Switch off the car engine and detect the fuse box.
  • Locate the unpainted metal exterior surface. Then place your tester on that surface. Note that this is an important step.
  • Probe the fuses with your device.
  • Your stationery fuses will light up while your vehicle is off. Please do not connect your car stereo to the fuses. Also, note that switched fuses won’t light up; you will have to connect your stereo to the fuses. 

Stereo System

When your car battery suddenly drains out, even when you’ve long installed your car stereo. The stereo could still be the reason for the battery drainage.

In this condition, you should focus on your stereo system. Before figuring out how to end this problem, you need to understand how the stereo system works.

The stereo has many relays that are transmitted in the circuit boards.

The internal circuit board is an important component of a stereo. With time, the system will become less effective. Some relays might get damaged or wear out.

Due to this, the stereo system might not sleep when it should, which can lead to a wastage of energy, which drains your battery.

When your stereo is in very good condition, there’s a chance for it to still malfunction in a way that’s challenging to detect. 

How to Fix

If one of your relays is damaged, you have to change it and get an EPAuto Relay. That’s the best way out.

Repairing your relays is possible; we don’t advise you to go through that as the process is extremely difficult, requiring a lot of time, effort, and professional touch.

Detecting a faulty can also be difficult. You may not be able to direct the fault to the relays. Even when found, you will have a tough time repairing them.

We recommend that you will have to change your stereo in this situation. This way, you will completely deal with this issue. Then ensure you go about the installation process correctly.

Incompatible Battery 

Another reason your car stereo drains a lot of battery is that your battery is not capable enough to handle the stereo system.

This shows that your stereo needs more amperage than your car battery is supplying.

You can face this condition when you have installed an aftermarket stereo in your car.

The stereo can require a high-power demand from your alternator, and due to this, the alternator will have a tough time recharging your battery while your vehicle is running.

“Outrunning” is commonly used to address this problem.

How to Fix

The best approach to get rid of this problem is to either use a large battery or buy an extra battery for your vehicle.

Changing your old battery to a bigger-sized one can be challenging.

Sometimes it is impossible to do this, as your new battery might not fit in your car.

You might also need to engage in many things to finish the installation process. But when placing a larger battery in your tray is possible, you can use this method.

Suppose your stereo needs a higher power source, then you need an additional battery. You can continuously use your extra battery while your vehicle is not moving.

It’s best to install an additional battery that has heavy parts. With this solution, your stereo will get the needed power while the main battery is not disturbed.

You must ensure that your old and new batteries are installed in parallel.

You have to purchase healthy batteries like the Odyssey or ACDelco battery to get the best performance.

Although getting a new battery isn’t compulsory, it certainly makes a difference.


Can A New Radio Drain My Battery?

When you buy an aftermarket stereo system, it is most likely for your car battery to get drained. The issue usually has to be with the fuse. Most of the aftermarket radios are made with bad fuses that surely wear out or break, which can cause sudden drains from your car battery.

Can A Faulty Radio Drain a Car Battery?

Operating your car radio while turning off your engine can drain your battery, but this is not very likely in modern cars. If your vehicle doesn’t start after listening to the radio with your engine turned off for a long time, you will have a big problem. Your best option is to use another battery to start your vehicle, replace your dead battery, or jump your battery.

Why Does My Car Battery Die After Sitting For A Few Days?

If your car battery dies after leaving it to sit for a few days, you will need to replace it. It died either due to age or a parasitic drain. A poor wired radio, a bad relay, or a mobile phone charger plugged in for some hours can drain your car battery power while your vehicle isn’t powered.

What Could Be Draining My Car Battery?

Excess current can be drawn due to short-circuiting, which can drain your battery. Inspect your charging system for a damaged or loose alternator belt, faulty alternator, or any other problems in your circuit. Engine problems can also lead to excessive battery power drainage.

Why Does My Car Battery Keep Dying Overnight?

Some of the popular reasons for your car battery to die continuously are when you have a corroded battery connection, charging issues, constant electrical drains, persistent demand for high power than what’s provided by the alternator, and harsh weather conditions.

Final thoughts

We hope you can answer the question; can a car radio drain your battery?

While attempting to fix any issue, you need to be very careful. We advise that you do not start any repairs if you have any knowledge of cars.

But with our guide, it shouldn’t be challenging. This problem is 100% fixable.