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A lot of people worry that listening to the radio in the car with the engine turned off could drain the battery.
In theory, leaving the radio on while the engine is off could drain the car battery. However, radios usually don’t use a lot of power, so battery drainage is more likely to be caused by other things such as lights, fans and heaters.
Having the heating on while the engine is off is much more likely to drain the battery than leaving the radio on.
The amount of battery power your radio uses will depend on the audio equipment you have in your car.
If you have a lot of powerful speakers or a power-hungry subwoofer, it will drain the battery much quicker than if you just have a regular car radio.
Also, if your radio has a large screen and you fiddle with the controls a lot, it will drain the battery more quickly.
How long can a car battery last while playing radio?
If your battery is in good condition, you should be able to listen to the radio for hours without any problems.
Make sure to turn off heaters and lights, as these could cause the battery to drain quickly.
If you’re worried about the battery running down, it might be a good idea to use a portable radio in the car instead of the built-in radio.
Should you turn off the radio before turning off the engine?
If you’re driving a modern car, there’s generally no advantage to turning the radio off before turning off the engine.
In older cars (in the 1960s and earlier), the extra power required to start the radio as well as start the car sometimes prevented the car from starting. New cars are more powerful, and won’t have a problem starting the engine and radio at the same time.
If your car radio keeps playing when you turn the engine off, you will save a bit of battery power by switching the radio off before turning off the ignition, though it won’t make a huge difference.
Can the radio drain the car battery even when it’s turned off?
If the radio is switched off, it shouldn’t be able to drain the battery.
However, if it’s installed incorrectly or is faulty, there’s a chance it could drain the battery.
If this is happening to you, make sure the radio is wired properly.
Since it’s very unlikely that your car radio would drain the battery even when turned off, it might be a good idea to consider these other possible explanations:
- Check that the radio really is turned off, and not just silent.
- The battery might be getting old.