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How To Fix a Dead Car Battery in 9 Easy Steps

Are you stranded with a dead car battery and feeling helpless? Fret not, as we have got you covered! A dead car battery can be a frustrating experience, leaving you with no choice but to halt your plans. But don’t worry, there are plenty of solutions to fix a dead battery and get your car running again in no time.

In this guide, we’ll provide you with detailed information and simple step-by-step instructions on how to fix a dead car battery. So, sit back and relax, and let us guide you through the process.

How To Fix a Dead Car Battery?

1. Jump-starting the battery

To fix a dead car battery, you can jump-start it using a portable jump starter. Here’s how to do it:

Step 1: Turn off the car and remove the keys from the ignition.

Step 2: Locate the battery and identify the positive and negative terminals.

Step 3: Make sure the jump starter is turned OFF before connecting the clamps to the car battery.

Step 4: Connect the positive clamp to the positive terminal of the car battery.

Step 5: Connect the negative clamp to a grounded metal surface on the car, such as a metal bracket or the engine block.

Step 6: Turn on the portable jump starter and wait a few seconds.

Step 7: Start the car. If it doesn’t start immediately, wait a few more seconds and try again.

Step 8: Keep the engine running for a few minutes to allow the battery to recharge.

Step 9: Once the car is running smoothly, turn off the portable jump starter.

2. Charging the battery

Charging a dead car battery is an important task that can be done in two ways. The most convenient solution is to use a battery charger which you can connect to the battery and turn on and then wait until the charger indicates that the charging process is complete.

Alternatively, if you’re feeling more adventurous, you could start the car and drive it for at least 30 minutes – the alternator naturally charges the battery during this time. In either case, having a charged battery is essential for any car owner so make sure to find out what solution works best for your situation!

3. Cleaning the battery terminals

Before you take loose the battery and run out to buy a new one, consider that corroded or dirty battery terminals are often the culprit.

To fix this problem yourself and save money, you’ll need baking soda, water, and a wire brush. Start by removing the cables from the terminals then mix baking soda into water until you create a paste.

Apply the paste with the wire brush to both the terminals and cable ends then scrub until they are clean. Rinse with water, then dry them off with a clean cloth to get your car back up running again!

4. Checking the alternator

Are you dealing with a dead car battery even after trying to recharge it? Chances are, the problem may lie with the alternator not charging the battery.

To verify this and see if you need to replace the alternator, all you’ll need is a multimeter. Start by turning your car on and turning on the headlights.

Then set your multimeter to read voltage and check by touching the probes to your battery’s terminals. The normal reading should be between 13.5 and 14.5 volts; any lower readings means that your alternator needs to be replaced in order to fix your problem of how to fix a dead car battery!


Common signs of a dead battery in a car

  • A slow engine crank when attempting to start the car
  • Dim headlights or interior lights (or no lights) when the key is turned in the ignition
  • Weak or non-existent sound from the starter motor
  • No electrical power, such as odd behaviors from accessories like radio, windows, etc
  • Swelling, bloating or bulging of the battery case
  • Battery fluid leakage.
  • Sulfur smells coming from the engine bay
  • The battery posts or terminals are corroded or covered with white powdery residue




How to fix a dead car battery can be a tricky thing to figure out. One potential cause is age – when a car’s battery has been in use for 2-5 years, sulfation can occur.

This is when sulfate crystals coat the negative plates in the battery and build up, reducing its power delivery and preventing your car from starting. Whilst replacing the battery might seem like an expensive undertaking, it will help to ensure your vehicle runs as it should and could save you time and money in the long run.

2. Mistake made by the user

How to fix a dead car battery when it’s a simple user error? Most of the time, preventative steps are better than trying to fix the problem after it has already happened.

Accidentally leaving an overhead light on, leaving something charging in the accessory power source, or using too much accessory power when you’ve only driven a short distance can all be causes for a dead battery.

3. Poor Charging System

If your car’s battery warning icon illuminates while you’re driving, it’s possible that the issue isn’t related to the battery itself, but rather with a malfunction within your vehicle’s charging system.

Poor charging systems can cause a variety of issues and render the battery completely useless. To be sure of the problem, it is best to have a qualified mechanic assess your alternator, serpentine belt, battery cable and terminals, and alternator belt for proper function.


If you’re trying to fix your dead car battery, one of the first places to inspect is any potential corrosion on the battery terminals. Corrosion can occur over time from dirt or dust buildup, or acid leaking from the battery itself. It can be identified by white, ashy deposits between the posts and cables of your battery.

To remove this type of residue, use a wire brush and baking soda. If you need further assistance with how to fix a dead car battery due to corrosion, it is best to seek the help of a professional.

Related: How To Clean Corroded Battery Terminals


How To Restore A Car Battery

Here’s a revised version of the step-by-step guide to reconditioning a battery:

1. Prepare for the process

Make sure you’re working in a well-ventilated area and wear protective gear.

2. Make a cleaning solution

Mix baking soda and water in a 2-to-1 ratio to create a runny paste. This will serve as a battery cleaner and an acid spill cover-up.

3. Clean the battery 

Apply the cleaning paste or a dedicated battery cleaning product to the corroded battery terminals and scrub the build-up off with a toothbrush. Use steel wool for heavily-corroded batteries. Clean, wipe, and dry off the terminals completely.

4. Check the voltage

Use a voltmeter to check the battery’s voltage. A healthy battery will read 12.6V. Between 10V and 12.6V means the battery can be reconditioned, while less than 10V requires replacement.

5. Empty the battery cells

Remove the battery cover and cell caps underneath. Slowly empty the cell contents into a bucket, neutralize the battery acid with baking soda, and dispose of it at a recycling center.

6. Clean the battery cells

Pour the cleaning solution into each cell, shake the battery, and dispose of the mixture.

7. Replace battery cell solution

Mix water and Epsom salt, refill the cells with the new electrolyte solution, and re-shake to distribute the salt.

8. Recharge the battery

Place the charger in a safe area and connect it at a speed of 12V / 2 amps. Let the battery recharge for 36 hours.

9. Test the battery

Use the voltmeter to check the battery’s status. Charge it again if the reading is low. Perform a load test by turning your vehicle to the “On” position and with the high beams on. If the voltmeter readout lists 9.6V, the battery is successfully reconditioned.

Be proactive, not reactive

It’s far too common to find yourself in a situation where you need to know how to fix a dead car battery. No matter the situation, it’s always better to prevent damage than repair it. The best way to do this with your car battery is through regular maintenance and inspections.

Having an annual checkup can help keep your battery happy and healthy for many years so you will not have to worry about the potential for emergency repairs or having to buy a new one.


Can a Battery Be Too Dead to Jump?

Yes, if the alternator is not functioning properly and is unable to charge the battery, jumping will not help.

What are the signs of a failing battery?

Common signs of a failing car battery include difficulty starting your car, dim headlights/interior lights when turning on, corrosion around your terminals, or swollen sides on your battery.

Is it dangerous to jump start a car?

Incorrectly jump starting your car can cause serious damage to both cars by creating sparks or short circuits so it’s important to be familiar with the process beforehand.

Make sure you consult an expert if you’re unsure about any step in the process!

What is Battery Sulfation?

Sulfation is a chemical reaction that can occur in lead-acid batteries due to overcharging or leaving the battery unused for an extended period of time. This reaction causes a buildup of sulfate crystals on the battery’s plates, reducing its ability to hold a charge and eventually leading to failure.

Regular charging and maintenance can help prevent sulfation from occurring!

Can Battery Sulfation Be Reversed?

Yes, sulfation can be reversed with a process called desulfation. Desulfation involves charging the battery at a very high voltage to break down the sulfate crystals on the plates and restore their original condition.

However, it’s important to note that this process should only be done with professional equipment as incorrect voltages may cause damage to your battery.

How Long Can a Car Battery Be Dead and Still Be Recharged?

A car battery can still be recharged after being dead for up to two weeks. After this time frame, you may need to replace the battery as it may not hold a charge anymore.

If your battery is over 2 years old, it’s best to get a professional inspection or replace the battery altogether as age plays a big factor in how often batteries fail.

Should You Remove the Battery from a Car When Not in Use?

If you plan on storing your vehicle for a season, it is highly recommended that you remove the battery entirely. A good way to do this is to place the battery in a battery box and place it in a dry, well-ventilated area with an optimal temperature of 40℉ to 60℉.

Doing so will help preserve its life and prevent any issue like a dead car battery when you are ready to get back on the road. Additionally, make sure to check the charge of the battery every month, and charge it if it ever reaches below 70%.


A car battery should last between two and five years, but sometimes they die sooner. If your car battery dies, you can replace it with a new one or try jump starting it with another car. You can also take measures to prevent your battery from dying in the first place, like driving less and turning off electronics when your car is idling.

Hopefully this article helped you understand how to fix a dead car battery or how to keep your current battery healthy for as long as possible.

1 thought on “How To Fix a Dead Car Battery in 9 Easy Steps”

  1. Jump-starting a dead battery alone will not resolve the issue. The battery needs to be charged, and if it fails to hold a charge, it is time for a replacement. Additionally, it is not advisable to charge a dead battery with your alternator after jump-starting, as this can place a significant strain on the alternator. This excessive strain, combined with a deeply discharged battery, can potentially damage an otherwise functional alternator.


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