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Car Battery Is Dead: 12 Reasons Why Your Car Battery Keeps Dying

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

Car Battery Keeps Dying

Car Battery Keeps Dying

Cars used to be easier before being electrical.

Cars becoming increasingly electric dependent is causing consumers to make mistakes that could cost them plenty. The past is full of cars heavily dependent on mechanical action. In today’s world, most cars are electric in nature.

Electronics make cars complicated. Electrical and electronic devices all have one thing in common: they make things complicated. The answer is not straightforward when you find an electrical problem.

Checking the charging system and other solutions. There are steps and procedures to follow to find out why the car battery keeps dying. It is especially important to follow these if your car is dying overnight.

How to Stop Car Battery From Dying

1. The Radio is killing your battery

The first solution is to check up on your radio. Make sure your radio is off when turning off the car. This could cause issues when left unattended. Ensuring the radio stays off means your battery is not being discharged while you’re gone.

There are also times where the radio is simply causing a higher load on the battery than is feasible. This is typical for weaker batteries or batteries with bad connections to the terminals.

2. Your battery can’t hold a charge.

Batteries may lose the ability to hold a charge due to the nature of acid batteries. The possible reason for not holding a charge might be trivial though there are many reasons for it not holding a charge. Having a failed or old battery means it is not able to hold a charge. As a result, you will not start your car.

3. The battery is leaking acid.

Batteries are composed of a sulfuric acid and distilled water mixture. This is how your car battery is able to hold a charge. Your battery will decrease in performance if it is leaking battery acid. It will seize to hold a charge at some point. It may cause your car to not start.

4. The battery is dry.

You need to ensure all non-maintenance-free batteries are properly filled with distilled water twice a year. Ensuring proper acid levels results in better battery charging and performance.

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5. Bad connection at battery posts.

Buildups of acid and other debris on the posts and terminals lead to lesser conductivity. The car will not start in severe cases due to the conductivity being unable to support higher amperage loads typical of starting a car.

6. Failed alternator not producing AC.

A failed alternator means a failed charging system. The alternator is responsible for converting mechanical energy to electrical energy in the form of alternating current.

7. Failed diodes

The AC generated by the alternator passes through three dedicated rectifiers (AC to DC) diodes. Improper charging and damage to the battery may result when the diodes have failed. AC may not properly charge a DC battery.

8. Accessories are being juiced when the car is off.

Accessories left alone may drain the battery over time. Improperly wired accessories commonly cause this. It is best to ensure accessories are not running while the vehicle is off – especially the accessory cigarette lighter port.

9. Accidental shorting of battery due to bad wiring.

Another common cause is accidental shorting of the battery due to bad wiring. You may experience the battery being drained by allowing staggering cables to touch both the positive and negative leads. This discharge the battery slowly because wires are a natural resistance source. Resistivity calculations may be used to demonstrate the relationship between bigger wires and higher resistance levels. Resistance makes the voltage drop and drain.

10. The headlights are not automatic.

It is possible you may not be aware that your headlights do not automatically turn off. Not all cars are equipped with this feature. I notice this feature on the newer models and not on the older ones. Turn the headlights off manually if you must.

11. The turn signal switch assembly is broken.

The headlights may turn on and off if the turn signal switch assembly is broken. It is possible the broken assembly is turning on your headlights or other sets of lights as you are leaving your car.

12. The headlight relay/switch is shorted and stuck to on.

The relay and switch to any light components may be accidentally stuck on in rare cases. Check all fuses and relays as a last measure to ensure this isn’t a problem.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2022 electronicsguy

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