If your car does not start, it might be a sign of a dead or dying battery. Alternatively, the connection cables could be loose or corroded, or an alternator could malfunction. There are many more reasons why your car doesn’t start, but we will focus on the ones caused by a dead battery.
Summary
The most common symptoms of a dead car battery are dim headlight and a slow crank. To tell if the car battery is dying, it’s important to see if the engine is slow to turn over and the battery is getting older.
In this article, we’ll also take a look at the following topics:
- What’s the best tester out there?
- How do you know what battery size you need?
- How do you replace it?
Continue reading
You should go to your nearest auto repair shop if you notice something wrong with your vehicle. The mechanics should run a test on your car to determine the cause of your problem. If it fails the test, you can replace it with their help.

But not all batteries will warn you about possible failures. A dead one will usually prevent the engine from starting, so this is one of the main symptoms that make things obvious. But if you are still confused, we will present you with 5 dead car battery symptoms and how you can tell if it’s dying.
Table of Contents
- 5 signs your car battery is dead or dying
- Signs of a bad car battery vs. alternator
- DIY replacement
- How to know what battery your car needs: battery group size chart
- Best car battery tester
- Conclusion
- FAQ
5 signs your car battery is dead or dying
If you suspect your car battery is dead or dying, there are some specific symptoms you can look for. With these, you can confirm the problem and take further action to repair or replace it.
Are you experiencing any of these 5 symptoms in your car?
- Dim headlights
- Clicking sound
- Slow crank
- Having to press the gas pedal to start
- Backfiring
Dim headlights

It is one of many symptoms showing that your car battery is dying. When you turn on the headlights, the component will not be able to power your vehicle’s electrical components fully. If the headlights are dimmer and weaker than usual, make sure to mention this to a specialized mechanic.
Dimmer headlights can put your safety in danger, especially at night. You will need optimal visibility during the dark hours of the night, and a dead one will prevent you from driving safely.
Clicking sound
The battery will send an electrical current to a component in your car when you turn your key in the ignition. If it is failing, it will have difficulty performing this action as the electrical current sent to the starter will be weaker.
The clicking noise you are hearing appears as a result of the starter receiving insufficient power from the battery. You can jumpstart the component and fix this problem temporarily, but this is not a long-term solution.
Slow crank
After years of driving your car, you become sensitive to any changes within the engine. You will notice every clicking sound and be more receptive if your engine cranks more slowly. When you turn the key, the sound might be different, which is a sign of a dying battery.
It is important not to ignore this warning and follow up with a skilled mechanic that can give you specific advice tailored to your own car’s needs.
Pressing the gas pedal to start
For starting the car, you shouldn’t have to press the gas pedal to start it. If you cannot start the car, try pressing this pedal. A failing battery might still turn on your engine if you press on the accelerator, but make sure to keep your car in neutral.
Backfiring
It is one of the most important warning signs. A failing battery will generate intermittent sparks, which can lead to fuel accumulation in the cylinders. When this fuel is ignited, it happens suddenly with a massive force that causes your car to backfire.
While backfiring could signify a failing battery, this is a common symptom of several other problems. Make sure to thoroughly check your vehicle’s condition and identify any other additional problems.
If you cannot bring your vehicle to an auto repair shop, there are some things you can do in the meantime. Cleaning your batteries will help. Focus on eliminating the corrosion generated around the terminals. The corrosion stops the battery from having a smooth connection.
While a dying battery is not necessarily an urgent issue, a dead one is a critical problem. You should replace it as soon as possible, but make sure to purchase one compatible with your vehicle.
Signs of a bad car battery vs. alternator
Suppose you are unsure whether the battery or the alternator causes the problem. In that case, there are specific symptoms to look for in each of these components. For example, your dashboard lights will dim if the component is drained. Proceed by turning on your windshield wipers or headlights. If they fail to start, your battery is dying.
Additionally, you can check for corrosion. If there is corrosion in your terminals, clean them with a rag and carefully wipe away any corrosion. Have someone help you and jumpstart it. Leave the engine running for a while and then turn the car off.
Next time you restart the engine, it should be working properly. If your car still fails to start, then this is a sign that the alternator is functional. It keeps the battery working when the motor is running. But when you shut down the engine, it isn’t retaining any more charge with the alternator stopped.
If you can’t find a problem with the component, it is time to check the alternator for possible problems. For example, the brightness of the interior lights can change if there is a problem. If your dashboard gradually dims, the alternator might be damaged.
The car headlights might run brighter than usual when you accelerate the car but will dim down once you reach a full stop. It is another sign that the alternator is not keeping the battery fully charged.
DIY replacement

If you are sure that the model is compatible with your vehicle, you can order one online. After delivery, it is up to you to install this component manually. Fortunately, the process is simple and easy, and it can be done by amateurs and experienced mechanics as well.
All you have to do is follow the steps below, as we will show you how to replace a car battery by yourself. Make sure to follow every step and don’t skip any of them, as they are all essential.
How to replace a car battery yourself
- Find the car battery.
Turn the engine off and put the car in park. After you remove the key, wait a couple of minutes for the engine to cool down. You do not want to work with an overheated engine which might also put your safety in danger.
Open the hood and locate the battery. Depending on your vehicle, the location of this component can vary. Most are situated in the front and mounted on a metal tray.
But some cars will have this component placed in the trunk. Check the owner’s manual if you are still unsure about the exact location of your vehicle’s battery. - Locate and disconnect the battery terminals.
All batteries will have two terminals used for connecting the cables. Plastic covers might be used to cover them, so make sure to remove them first. These covers are painted in black and red, signifying negative and positive.
After removing these covers, the terminals will be marked with a plus for positive and a minus for negative. You should always disconnect the negative cable first. Work gloves and eye protection are also necessary, as safety is your number one priority.
Use a wrench to loosen the bolt holding the negative connector to the terminal. Once you remove this bolt, twist the cable connector until you can remove it from the battery. Repeat the same procedure with the positive terminal as well. - Remove the old battery.
A metal bar will secure the battery. Loosen the bolts that secure this bar and remove it slowly. It should be exposed now, and you can easily remove it from your engine block. Keep it upright while doing so, as batteries have caustic liquid inside them.
- Clean the battery tray and terminal connectors.
The terminal connectors can corrode with time, and now you can clean them thoroughly. Use a battery cleaner and a strong wire brush to clean the tray. You can also use a baking soda paste for doing so.
This paste is made out of two tablespoons of baking soda and a teaspoon of water. Clean the inside connectors thoroughly and leave all the components to dry naturally. - Install and secure the new battery.
Make sure the position of your newly installed battery matches the red and black terminals. You don’t want to get the terminals wrong. Place this component into the mounting shelf and re-attach the hold-down bar by tightening the bolts that secure it.
Apply a special anti-corrosive protection gel on both terminals before connecting the cables. After that, connect the positive cable to a new battery first.
Push the connector all the way down on the terminal and tighten the bolt. Start with the positive cable first and repeat the same step for the negative one.
How to know what battery your car needs: battery group size chart
There are various kinds of batteries out there, and we created a chart to show you the different sizes. You can use this information to identify the best one for your car. You can also make sure to choose the model that fits your vehicle.
Battery type | Suitable cars |
65 – top terminal | Ford, Lincoln |
75 – side terminal | Chrysler, Dodge |
24/24F – top terminal | Lexus, Toyota, Nissan |
34/78 – dual terminal | Chrysler, Dodge |
35 – top terminal | Toyota, Nissan |
Best car battery tester
What is a car battery tester? It is an important tool to check the health of car batteries. Check out some of the best ones below.
FOXWELL BT705 12V 24V Car Tester Automotive 100-2000 CCA Alternator Load Testers

This tool was created by the famous company Foxwell. It aims to analyze specific issues. This analyzer has been developed to test spiral and gel, and AGM batteries with a capacity of up to 2,000 CCA.
If the battery is dying, the tool can easily diagnose this problem. Additionally, you can use this tool to detect the failure of charging systems in cars, boats, or even motorcycles. Most of these issues can be diagnosed with the Foxwell BT705 tool.
It is a quick and easy solution to check your battery’s health at an affordable price. You won’t need to get the help of a skilled mechanic at an auto repair shop. This tool will tell you exactly what’s wrong with the electrical system.
Name | 12V Car Battery Tester Battery Load Tester |
Brand | FOXWELL |
Item Weight | 2.88 pounds |
Life-long Updates | ✓ |
Print Diagnostic Data | ✓ |
Product Dimensions | 13 x 3.2 x 9.1 inches |
Pros
- Foxwell has been around for a long time.
- It’s easy to use
- Very comprehensive information
- Fast
Cons
- It’s not the cheapest option out there.
- Customer support could be better.
Commercial or personal use

You can use this tool both for commercial or personal reasons. It comes with a multitude of features, and they will be ideal for your automotive needs. A battery health monitor will check the cold cranking capability.
At the same time, it can determine the exact aging status of your battery. This way, you will know exactly when to replace the component before it is completely depleted. You can determine your alternator’s health by testing your vehicle’s charging system.
This way, you will avoid damaging the component because of an overcharge. The tester can easily detect changes in the battery voltage and determine the alternator’s condition. However, it cannot test the alternator directly.
You can check the cranking system as well. Firstly, you should make sure that the generator is in regular condition. Then you can use this tool to detect if the generator provides sufficient power to the electrical system. Lastly, check if the component can hold the charge as well.
This highly practical tool can test various batteries, from 24V ones to AGM spiral models. You can test the batteries on the car directly under the hood without needing removal. It is a significant advantage for commercial use, as mechanics can check multiple cars quickly.
You can check the battery’s health with this tool and the state of charge and internal resistance. Voltage and CCA rating are also parameters that can be determined by this tool.
Results in 3 seconds
Results appear in just 3 seconds with an accuracy of up to 99.99%. Bad cells will be detected directly, and you can take further action to replace them. The Foxwell BT705 does not emit heat or light, keeping the operations safe for all types of usage.
Your battery will not be discharged as sparks will not be generated. Automatic temperature compensation is ensured by a special function that places this tool above its competitors.
Good LCD display
It is extremely easy to use, and the LCD display features backlight technology. It is operated through different menu options, and the sleeve is rubberized for better grip. A 7.8 feet tester cable with metal alligator clips is stored inside.
When measuring with this tool, you will get 3 different kinds of diagnostics. The “good battery” message signifies that yours is in good and optimal condition. The “good-recharge” message reassures you of the same optimal condition but warns you about a low current level.
If the diagnosis reads “charge & retest,” a full charge of the component is necessary. Lastly, the “replace battery” message warns you about its depleted state, which needs immediate replacement. You can also disconnect the cables and retest them out of the vehicle to make sure.
In the case of a damaged component, the “bad cell-replace” diagnosis will be shown on the screen. The component is beyond repair in this situation, and immediate replacement is mandatory.
Overall, this is an ideal tool to have in your garage. It will prove to be essential when you start encountering the symptoms presented above. This way, you will know if your vehicle’s problem comes directly from its battery.
Customers are satisfied with this product, and the company still delivers its promises. They are also highly focused on customer support, so they will always answer any questions you have regarding their product.
Brand | 24V 12V FOXWELL |
Item Weight | 2.88 pounds |
Print Diagnostic Data | Yes |
Product Dimensions | 13 x 3.2 x 9.1 inches |
Pros
- The information you get is comprehensive.
- It’s easy to use.
- It’s lightning fast.
- The carry case is high quality.
Cons
- Setting CCA you have to push the button for the next numerical value
Conclusion
If you’ve experienced one of the symptoms listed below, it’s time to get your battery checked:
- Backfiring
- Having to press the gas pedal to start
- Slow crank
- Clicking sound
- Dim headlights
FAQ
They cannot recharge themselves, regardless if they are healthy or dead. They require an additional external power source to get charged. But once it is dead, the alternator will fail to recharge it again.
You will have to jumpstart your car to keep it running temporarily. Take your vehicle to the nearby auto repair shop, and professional mechanics will use special chargers for your battery.
There are a couple of signs you can look for to determine if it needs replacing. Pay attention to these clues, and take immediate action if you notice them happening in your vehicle.
– The engine is slow to turn over
– The windows roll slowly
– Your battery is old
– Corrosion is present
– The dashboard lights flicker
– The headlights are dimmer
While this is not a common procedure, some methods can bring a dead one back to life. However, it will never reach the 100% capacity it had before depleting completely. A fall in productivity will make things worse in the long term.