Does Playing Music Drain Your Car Battery?

Your car radio isn’t just a source of entertainment; it’s also a ticket to real-time news updates, traffic, and weather info. And just like the heating or air conditioning system, it requires electricity to run. So, does playing music drain your car battery?

Playing music can drain your car battery if the engine is off because the alternator isn’t running to recharge it. However, your car radio doesn’t consume a lot of power unless you have powerful speakers and subwoofers. You can get up to 10 hours of listening time before the battery runs out.

The battery is usually fully charged or close to a full charge when you start the engine. And no matter how many components you’re using, the alternator will strive to replenish the battery provided the engine is running. Let’s get started so you know how the battery can get drained and what to do if it happens.

Will Listening to the Radio Drain Your Car’s Battery?

Listening to the radio can drain your battery only when the engine is off because the battery isn’t getting recharged at that time. However, your car radio doesn’t draw much power, and you can play it for as many as 10 hours before the battery dies out.

Your car battery works as an energy storage point, and it usually gets recharged by a device called an alternator, which is connected to the engine. Provided the engine is running, the alternator produces enough energy to keep all electrical systems like the AC running on top of charging the battery. It also powers electronic components like your radio and GPS.

But when you turn off the engine, you can only power a few systems with the battery. The electricity stored in the battery gets used without any source to replenish it.

Generally, playing the radio for a short time when the engine is off shouldn’t have a massive impact on the battery. On average, car batteries have a capacity of around 60 Ah (ampere-hours), meaning they can provide 60 amps of current for 1 hour or 6 amps for 10 hours.

So assuming your battery is in good shape, you’re only using the radio and it draws 6 amps of current, the radio can play for as much as 10 hours before losing the satellite signal. 

In a practical sense, however, how much battery power your radio consumes also depends on your car’s audio system. If you have a power-hungry subwoofer or speakers, the battery will drain faster. The same goes for radios with large displays.

What About Listening to Music via Aux Cord?

Whether or not the engine is running, your audio system is always drawing power when it’s playing. That said, your battery will still drain if you’re listening to music via the aux cord when the engine ignition is off.

Your aux cord is only feeding low-voltage audio-frequency signals to the music player, but the latter needs a significant amount of electricity to play music. Since it draws that from the battery and the battery isn’t getting recharged, it will deplete with time.

Do Gas-Powered Car Batteries Drain Faster Than Electric Ones?

Gas-powered car batteries drain faster than those found in electric cars because they’re conventional lead-acid or nickel-metal hydride batteries with a lower capacity. Moreover, they only get recharged when the engine is running.

Conversely, EVs use lithium-ion battery packs, which are more resilient and have a higher energy density. They self-discharge at a slower rate and can provide more consistent voltage levels even as the charge degrades.

EVs are powerful enough to take you on the road for hundreds of miles, and they don’t have limitations on the electronics even when you’re not driving. 

Moreover, electric car manufacturers develop software to monitor battery health and pair it with dedicated hardware to improve the battery’s efficiency and safety.

What to Do if Your Car Battery Runs Out

If your car battery runs out, you can revive it by sharing the power of another car with a healthy battery. You can also use the help of a few friends to help you bump-start it if it’s a manual car. However, these fixes don’t apply to hybrids and EVs —  and they can actually cause serious damage.

Jump-starting is the human equivalent of CPR, and you need to do it safely without killing the battery of the second car. Follow these steps:

1. Park both cars nose-to-nose or side by side without their bodies touching.
   
2. Ensure the ignitions of both cars are turned off and the parking brakes are engaged.
   
3. Connect the positive (+) terminals of both cars with the red jump lead.
   
4. Connect the black jump lead to the negative (-) terminal of the charged, active battery.
   
5. Connect the other end of the black jumper cable to the grounding point on the dead car. The grounding point is an unpainted, bolted-on metal part on the engine block or chassis.
   
6. Check all the connections to ensure the positive lead isn’t touching any metallic part of the car.
   
7. Turn on the working car and let it run for 10 to 15 minutes.
   
8. Now turn on the car with the flat battery. 
   
9. Let both engines run idle for 5 minutes, then turn them off.
   
10. Disconnect the leads in reverse order, starting with the black one and removing the red one last. The leads shouldn’t touch any metallic part of the car as you remove them.

11. Start the car which had a dead battery and drive for at least 30 minutes to recharge the battery to a safer level.

If you drive a manual and don’t have access to jump leads or a car with an active battery, you can “bump-start” it as follows:

1. Ask a few people to help you push the car and let them gather behind it.
   
2. Switch off everything that might drain your car battery.
   
3. Press the clutch to the floor and disengage the parking brake.
   
4. Ask your friends to give you a push.
   
5. Once you’re rolling at 5 to 10 mph, turn on the ignition and release the clutch gently when the engine starts.

You might have to repeat these steps a couple more times before the engine starts. But once the engine comes to life, be sure to drive for at least an hour to recharge the battery.

To avoid all this hassle, you can invest in a portable jump starter kit that you can store in your trunk to ensure you never get stranded in the middle of nowhere.

How to Preserve Your Car’s Battery Life

To keep your car’s battery in good working condition and have it serve you for longer, you’ll need to do some upkeep.

Here’s some tips for preserving your car’s battery life:

Test the Battery’s Voltage Every Month

Your car’s battery life can shorten dramatically if you leave it partially or fully discharged for long periods. As such, you should test its voltage level with a digital multimeter at least once a month to know its health.

A healthy, fully-charged car battery should have a voltage of around 12.7 V. But if it drops below 12.5 volts, it’s time to recharge the battery. If it keeps hovering around 12 V, it’s dead and you need a replacement.

Limit Power Use When the Engine is Off

Your car battery is healthy and happiest when kept close to a full charge, so using the infotainment system and leaving lights on when the engine is off is a big no-no. Before leaving the vehicle, double-check that all electronics are off. 

And if you tend to forget to turn off the lights, you could post a reminder on your dashboard or park in a direction where you must walk past the headlights. 

Keep the Battery Clean and Corrosion-Free

A heavy buildup of grime and corrosion material can become conductive enough to make the battery discharge across the high-resistance path on its casing. This will eventually flatten the battery.

Inspect the battery regularly and clean it when you notice dirt buildup and corrosion at the terminals. Scrub the battery terminals with a wire brush or hard bristle toothbrush dipped in baking soda paste. 

Rinse them thoroughly with distilled water and wipe them dry. Be careful not to let the baking soda and dirt residue get into the vents.

Always Keep the Battery Tightly Fastened

Excessive vibration can create short circuits and damage the battery’s internal components, reducing its service life. That said, you want to fasten the battery securely in its compartment. 

While at it, ensure you only tighten the battery clamp nuts until you feel the resistance start, as over tightening them will damage the battery. You can only go for an additional half-turn.

Minimize Short Trips

You give your battery some kind of workout every time you start the car, but then it gets recharged as you drive. If you only let the engine run for a short while, the battery might not charge completely to compensate for the lost power. 

Repeating this makes the battery voltage reduce steadily until you can no longer start the car. If you won’t be driving regularly or for longer periods, consider investing in a battery charger to help maintain the correct voltage.

Don’t Leave the Car Unused for Too Long

All car batteries will naturally lose their charge over time even when no components are drawing power from them. If you don’t drive for so long, the battery might run flat because it’s only designed to recharge when the engine is running. 

So, if the car will sit for more than a week, you might want to get a trickle charger to maintain the battery’s recommended voltage level.