dead car battery

6 Signs Your Car Battery is Dead or Worn Out

In Electric by Magnus Sellén2 Comments

dead car battery

A dead battery can cause you to be stranded in dangerous places if it is not replaced immediately.

The battery is not a permanent component of your car and must be replaced after prolonged use. The alternator and battery work together to supply power to all the car’s electrical accessories.

The battery also delivers some of the current to the stator and turns most of the engine’s components. But what are the symptoms of a dead car battery?

Symptoms of a Dead Car Battery

There are several symptoms that can indicate that your car battery is dead. The most noticeable is that the starter just clicks when you try to ignite it, but there are several others that are good to know:

1. Slow crank

If you notice that your engine takes time to start up, your battery may be flat. A good battery should last about 5 years. After that you will notice slow engine starts.

If the battery is empty, you may find that the car turns slowly and it is laborious. You must rule out the possibility that your starter could be the problem or that the spark plugs are worn out. To rule out a spark plug problem, check that the starter motor cranks at normal speed.

In cold weather – due to the battery draining – you might have problems starting the car. You can decide to weather the storm and wait for warmer weather or buy a battery that produces more amps. The problem could also be a parasitic drain, which you’ll need to identify.

2. Dim headlights

dim headlights

If you find that your headlights work as low beam even when you press the accelerator fully, your battery is on its deathbed. Headlights need a fully charged battery to shine well in the dark; it’s dangerous to drive with such headlights because you can’t see ahead and incoming cars can’t see you (especially in fog).

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This is especially noticeable when the alternator is worn out.

In addition, problems with the car radio or air conditioning system can also occur when the battery is empty.

3. Check engine light

There is a myriad of reasons for the check engine light to come on; an empty battery is one of them. If your engine light is on, you must use a voltmeter to check the battery voltage.

4. Clicking sound

The starter needs the current of the battery to drive the engine. When the current is weak, the starter motor does not receive enough power to start the engine and you hear a clicking sound under the hood.

An empty battery makes no noise when you press the ignition. However, there may be other reasons for this, and you must rule out faulty ignition switches, starter motor, and fusible link.

5. Backfiring

Closely related to a slow crank is the misfiring of the car. The battery can cause sporadic sparks in the combustion chamber, which can lead to the fuel-air mixture not igniting properly. This causes more fuel to accumulate in the combustion chambers, which is then passed through the exhaust chambers.

However, before replacing your battery due to misfiring, make sure that you have eliminated any other related problems.

6. Lack of dome light

If the battery is low, you will see a weak door light, but if the battery is dead, the door lights will not come on. If you replace the battery and the problem persists, the problem may be with the door wiring.

Why your car battery died faster than expected

There are several things that may shorten the life of your car battery. Here are a few of them:

Human error

One of the reasons for an empty battery is human error. There are moments when you are in a hurry and forget to turn off the lights or close a door. If the headlights stay on overnight or for a few days, they drain the battery and your car will fail to start. However, modern cars have warning signals when you leave the headlights on, such as a beeping sound.

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Faulty wiring

If you have bought a radio with large subwoofers, your battery may be constantly drained. You must first check the wiring and look for poor insulation. Alternatively, you may need to upgrade your battery to something more powerful.

Faulty alternator

The battery, in conjunction with the alternator, supplies power to the car’s electrical devices. When the car is moving, the alternator recharges the battery. Over time, the alternator starts to develop loose belts and eventually stops working. When this happens, your battery will stop charging fully and you will see signs of a flat battery.

A faulty alternator diode will cause the alternator to continue charging even after you have turned off the engine. In the morning you may find yourself with an empty battery.

Not driving the car frequently

If you do not make long journeys with your car, your battery will not become fully charged. The battery works together with the alternator to start the car, power the windows and the air conditioning. The battery is most needed when starting the car, but it discharges because it supplies power to most vehicle systems. The alternator constantly charges the battery when the car is moving.

If you only drive the car for short trips, you are denying the alternator the ability to charge the battery sufficiently; this is often the case in winter when the car heater is used a lot.

Battery corrosion

During periods of extreme weather, lead sulfate forms on the battery terminals, causing corrosion. These accumulations of lead can interfere with the smooth operation of your battery. A simple solution of soda or coke can be used to scrape off the corrosion. It is recommended to replace the battery every 4 to 5 years.

If you do not recharge your battery frequently, your battery will drain sooner.


If the car does not start, the battery may be flat. You must first check the door lights and headlights and see if they are working or dimmed. Loose wiring can be the cause of this, so it is extremely important that you rule out other causes of the car not starting. If you turn the ignition key and nothing happens, you could be dealing with a dead battery.

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Also check the ignition system. A multimeter is a device with which you can check the voltage of the battery. The low battery charge will cause a slow ignition. In this case, the battery has some charge, but not enough to start the engine. Jumper cables can help you start the car while you wait for the alternator to fully charge the battery.

Hello I'm Magnus, the owner and the writer of this website. I have been working with cars since I was 16 and I'm specialized with in-depth Automotive diagnostics. Also been driving drifting for the last 6 years. I'm here to give you answers to all your automotive questions and I hope that you enjoy our content.

2 thoughts on “ 6 Signs Your Car Battery is Dead or Worn Out ”

  1. Great tips! Thanks for sharing. Its essential to pick up the signs and signals your car is showing before you find yourself in a stranded position which could’ve been avoided with timely checkup. I would also suggest to have the number of a good roadside assistance service near where u live or go to work like i have On-Site Auto and Services near Port Orange. I have been saved a lot of time and hassle due to their quick service.
    But yes everyone should make a habit of taking their car for regular checkups.

  2. Car – diesel estate C Class 220 Mercedes-Benz 2007 W203
    Recently returned from Cornwall to Midlands – 700 miles. No starting problems. Last time we went. In it a few days ago. Needed ignition key to be put in twice before engine started. Today nothing when ignition key inserted. Lights work. Had car since June 2020. Battery not replaced though starter motor was. Any suggestions please. Possibly alternator?

  3. Due to a very high demand and high ammount of comments, you have to wait for some time for your car questions to get answered. If you want to get fast answers from a certified master technician you can ask your questions here:
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