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Why Does My Car Battery Keep Dying Every Night

Fernando the electronics guy is an electronics engineer. He earned his Bachelor of Science in Electronics Engineering from UC Riverside.

Why does my car battery keep dying? You check the battery and you're surprised what you find.

Why does my car battery keep dying? You check the battery and you're surprised what you find.

Why does my car keep dying?

Once upon a time, things were so simple.

Nowadays, all electrical components and electronics in your car are electrical-mechanical hybrids known as mechatronic devices. Even jump starting your car may cause damage, contrary to popular belief.

If your car keeps dying overnight, the easiest and best place to rule out the symptom is to check the charging system. Always start with the battery.

If you’ve ruled out the car battery and figure it keeps dying, you may have a bad battery.

Batteries are supposed to always be above 12 volts for optimal functionality of the vehicle. Go below that, and you risk malfunction of your precious electronics inside the vehicle. Going above that isn’t bad, either. A fully charged car battery sits around 12.8 volts, give or take on age and whatnot. Anything above 13 volts and you’re probably checking the battery while the car is on. Ensure to check the battery while the car is off.

Why does my battery keep draining?

If it drains too far, you’ll be complaining: “why does my car battery keep dying?” Your battery is draining for a multitude of different reasons. Not all of them are specific to your batter. Sometimes, your battery keeps draining for something simple such as your car stereo being left on.

Why does my battery keep draining? Here are a couple of reasons your battery may be draining:

If your car is on

  • Your alternator is not giving enough juice to the battery. It’s no wonder your battery keeps draining.
  • Parasitic drain above safe threshold. Either you have too much accessories and/or electronic or electrical peripherals. If the added measure of all of these drains is above the charging capabilities of the alternator, your battery begins to drain itself. This is rare.
  • Your alternator diodes are shot. The alternator is sometimes the culprit. The alternator’s diodes are meant to block current from flowing backwards. However, when the diodes are bad, the alternator and the battery are not isolated from each other – even when the vehicle is off. What ends up happening is the battery begins to short with the alternator. Thus, this may be a culprit.
  • Headlights or other lights. You probably forgot to turn something off. This is commonly the problem.
  • Your battery is bad. Go get your battery checked at autozone or oreilly auto parts.
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If your car is off

You alternator might be bad thus draining your battery. Or, your battery may not be able to hold a charge anymore.

Why is my car battery draining so fast?

If you know for a fact all headlights, as well as the stereo, are tuned on and the battery is draining faster than ever, your battery may be the culprit.

If in the case the battery is bad, it won’t be able to hold a charge. This is usually the culprit. The best recommendation in times like these is to find a new battery.

After replacing the battery with a new one, you’ll notice a marginally greater improvement in how your system is functioning. Even, you’ll be happy to know your car stops dying. And, your car battery isn’t draining at all anymore.

Why does my car keep dying: Conclusion

As you can see, there are a multitude of reasons your car battery may be dying.

  • Your battery is draining. Speak with a qualified mechanic and find out the root of the problem.
  • Your battery is bad. You can find this out by heading to a local automotive retail store. They may have the tools and equipment necessary to test your system.
  • Your peripherals are on. It’s never a good idea to keep lights, radio, and all sorts of other things turned on while the car is off. Ensure you’re practicing proper behaviors while the vehicle is off.

I hope you find what you’re looking for and figure out why your vehicle is dying. Feel free to comment on how this post helped you.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2022 electronicsguy

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