How To Test A Car Battery

Checking your car battery with having a good knowledge can lead you to succeed in knowing the right voltage

Car batteries are bound to stop working or even not perform as they would initially when they get to certain point of their lifetime.

Poor performance can also be caused by lack of regular maintenance by the car owner.

If you suspect that the car battery is not working as it normally would, like it may have a poor cranking response in the morning, you can test to see if the car battery is still able to perform well.

Do you know how to test a car battery? If not, you can follow these simple steps to check your car battery at home.

These can be done in either of the following ways:

Method 1. Using A Multimeter
Method 2. Using A Voltmeter
Method 3. Using An Ammeter
Method 4. Using A Battery Health Checker
Method 5. Using A Power Probe
Method 6. Using A Battery Hydrometer
Method 7. Using A Load Tester

If the car battery has been in use for about three to four years, then it would probably need to be replaced.

This is the normal lifetime of a car battery even if under well and proper maintenance from you as the car owner.

What Things To Know Before Testing A Car Battery

Before testing a car battery, you should be aware of the basics, such as how to use the results found to know whether the car battery is in good condition or not.

For instance, you should be aware that a good car battery should have a voltage reading of about 12.7 V.

A reading that is significantly below this, even after being charged, shows that the car battery is in poor condition and will have to be replaced soon.

You should also be aware of factors that may inhibit you from performing the battery testing methods effectively.

These include corrosion build up on the terminals which causes the terminals to not deliver power effectively to the car battery.

This also inhibit the battery from showing genuine test results. The “click” sound when you ignite your car might also indicate the state of the battery even before you proceed to test it.

1. Performing A Load Test

When you decide to perform the load test, you can begin by starting the car engine then turning on the headlights.

You can then leave them like this for approximately a quarter of an hour. After the fifteen minutes you can switch on the car and check on how bright the car headlights are.

A weak car battery will be noticed if the headlights are seen to get dimmer when the car engine is switched on.

A good, or rather reliable car battery, should be able to sustain the power demand of the headlights for more than fifteen minutes even as the car engine is switched on later.

It will be a good idea to buy a new car battery, to avoid being stranded on a road because the old one has died.

You can check out my best car battery reviews to choose which car battery will be the right fit for your car.

2. Checking For Corrosion

Corrosion builds upon the terminals of the car battery and thus prevents the supply of power to the car effectively.

In this case the car battery has to double its efforts in order to match the power demand of the vehicle.

This reduces the probability of the battery even getting to its expected lifetime. Corrosion also makes the car battery look rather unpleasant.

Corrosion build up on the car battery terminals can be cleaned using an old brush and a solution of baking soda. This can get rid of the corrosion incredibly fast.

It is important that you keep your car battery clean from corrosion before the build-up cannot be cleaned.

Some batteries get irreversibly corroded thus making them useless, meaning that you will just have to buy a new one.

3. Listening For Clicks

Whenever you ignite your vehicle engine, you should be keen to notice its response.

A car battery in good health will start quite easily with the least input effort. However, when you notice a “click” sound, then there is something wrong.

The thing with car batteries is that they get bad with time and they show signs that they are losing their reliability.

The “click” sound should act as a warning on just how much time your car battery is left with before its demise.

When you just hear a single “click” sound, then you might just be looking at a case of a poor car starter.

On the other hand, when the car makes three click sounds, the car battery might be actually dead.

Such type of batteries might be brought back to life with a jump starter, but they will not be reliable for long.

7 Ways To Check Your Car Battery {Let’s Learn Each Subject Deeply}

Testing your car battery is important so that you know its condition before using it. it is just like checking the gas or oil level.

These are all important if you want to go for a long journey and would not want to be disappointed with a “juice box” in poor condition.

If you use your car for commuting to and from work, you might need to test the car battery condition so that you can plan to buy a new one if necessary.

What Do You Need For Testing Your Car Battery?

The tools that you will need for testing your car battery depend on the type of test that you would wish to conduct.

The different ways of testing the car battery are discussed below:

Method1. Using A Multimeter

The multimeter indicates the power that the car battery potentially stores or rather, has. This is done by measuring the car battery voltage.

The procedure of using the multimeter are highlighted below:

  • Turn the car lights for some so that any surface charge will be gotten rid of
  • Place the multimeter to 15 to 20 volts
  • Switch the car lights off
  • Connect the multimeter to the negative and positive terminals of the car battery
  • If the battery does not show a voltage of about 12.6 volts, then it might be in poor condition
  • You can then have switched the car on and seek a revised voltage of over 10
  • If when the car is running and the voltage drops below the 5 level, then surely the car battery has been damaged

The damaged car battery is to be replaced as soon as possible so that you will not be stranded of even get late to meetings because of a car battery in poor condition.

Having a multimeter with you is advisable as it does more than other tools would.

For instance, when you compare the capability of the voltmeter and the multimeter, you will realize that the multimeter has unlimited usage.

Method 2. Using A Voltmeter

In the case of a voltmeter you can choose on either to work with an analogue or a digital voltmeter.

You should know how the voltmeter works so that you can be able to go through with this procedure successfully.

Before starting, the car ignition and all the lights should be turned off.

Next is to remove the cover on the positive terminal of the car battery. In the case that the car terminals are dirty, you will have to clean them before continuing with the process.

This will help get rid of corrosion build up that prevents the car battery from delivering power effectively to the vehicle.

Connect the positive terminal to the positive leadoff the voltmeter and the negative battery terminal to the negative lead of the voltmeter.

You can then check on the reading on the voltmeter. A car battery in good condition should show readings between 12.4 and 12.7.

Otherwise the car battery is in poor condition and is nearing its demise.

In some cases, the battery will indicate a reading of 12.4 and this means that charging it will enable the battery work better.

If lower than this, then you can charge it slightly then check the voltage reading.

However, for readings above 12.9, you will to turn the high beam to get rid of the excess voltage the battery has.

What Are The Differences Between Voltmeter And mMultimeter?

1. The voltmeter can only measure potential difference between two points in a circuit, while the multimeter directly measures the potential difference, current, resistance frequency and many more between two points in an electric circuit.
2. The voltmeter requires an ammeter to measure resistance in a circuit, while the multimeter does this directly.
3. The multimeter has numerous uses and could be used in any part of the electric circuit where the voltmeter is used, while the voltmeter can’t replace the multimeter.

Method 3. Using An Ammeter

The ammeter is used to measure flow from the car battery and is sometimes installed by some car manufacturers. It is used to indicate to the user the battery charging condition.

In the process it also shows whether the charge is flowing inwards or outwards of the car battery.

At times the ammeter shows if or not the generator is charging the car battery. A lower charge is seen in the case of a car battery in poor condition.

The ammeter is a better and recommended tool to use for testing the car battery especially for beginners as it shows results directly.

The ammeter is a good option to go for if you want a straightforward answer on the condition of the car battery.

You do not have to perform a series of calculations before you get to know whether you are dealing with a bad car battery or a good one.

Its simple nature makes it good for use when you want to check the condition of your car battery at home.

Method 4. Using A Battery Health Checker

Most new brands come with an already installed battery health indicator. If yours is an old one, you can have the battery health indicator installed in its system.

It is an important device for those who are aware of the process on how to test their car battery’s condition.

When the car’s ignition is switched on, there is an arrow that will point the division between the bands, that are either red or green. When it indicates green, then your car battery is in good condition.

Red, on the other hand, indicates that the car battery has been drained significantly and needs to be connected to a battery charger.

However, a dark black or transparent indication shows that the car battery is bad and needs replacement.

This is a direct way of showing the condition of your car battery and makes it amongst the option for testing the car battery at home.

Method 5. Using A Power Probe

This is among the fastest way of getting to know the condition of your car battery and it can be done in a fast and efficient way. This is also the easiest way of testing your car battery.

This particular method is opted especially when the temperatures are rather too cold when you want to test the condition of your car battery.

The process begins with the car owner taking out the positive terminal cover.

The positive lead of the power probe should be connected to the battery’s positive terminal while the negative lead to the negative terminal.

The Probe’s tip should then be attached to the positive terminal on the car battery.

Just like the readings of the voltmeter, a reading below 12.2 even after slightly recharging the car battery shows that the battery is in bad condition.

A reading close to 12.7 shows that you are dealing with a battery that is in good condition.

However, for a reading above 12.9, shows that the battery has excessive charge that needs to be controlled.

Method 6. Using A Battery Hydrometer

This is a rather different type of test when compared to the others; because it uses a fluid unlike others which use cables and meters to check the condition of the car battery.

This method uses the theory of measuring the gravity of the battery which can show its level of charge at the moment.

This method is not recommended in the case of a brand of car battery that is sealed.

The capacity being measured depends on the amount of plates that exist in each cell. Damage on the plates interferes with the cell’s capacity.

The hydrometer is able to tell the condition of the car battery by measuring the density of the electrolyte.

An electrolyte that is dense shows that the car battery has enough charge.

This method is not advisable for a battery that has just been topped; you should let it go through one charge and discharge cycle before performing this step.

This will enable the water mix with the electrolyte and will give the accurate results you need.

This procedure is performed by drawing the electrolyte into the hydrometer repeatedly to enable the thermometer adjust to electrolyte’s temperature.

You can then check on the reading. The reading is then analysed and you will be able to know the current voltage of your car battery.

Method 7. Using A Load Tester

Before going through with this process, you should ensure that the terminals are disconnected from the car battery to be tested.

The thin gage of the battery load tester that is the positive side should be connected to the car battery’s positive output.

On the other side, the negative thin gage should be connected to the negative output.

Some may come without a negative output, but they will have pin connector which is normally on the other side of the tool.

If you see sparks when you bring the pin connector in contact with the car battery, then the car battery is in good condition.

For a car battery that is in good condition, you will also notice that the rate of the voltage will drop to between 10 and 10.5 V.

A voltage reading below that, say 9V shows that your car battery is in bad condition and will need to be replaced soon.

If you need to replace your dead car battery, then this article will help you change a car battery.

Frequently Asked Questions

Now you know about my testing a car battery methods to see if your car battery is good or not.

With that, I will also provide you the list of the questions people often ask when it comes to checking a car battery.

Q1: How Long Does It Take To Test A Car Battery?

A car battery can be tested for at most thirty minutes. The duration taken during the process is determined by the type of test that is being performed.

Those that require a series of steps will probably last longer than the other types of tests.

Q2: Are Car Battery Tests Accurate?

Yes, they are. The results you get from the car battery tests are only accurate if you follow the right procedure of checking the condition of the car battery.

Some methods may turn out to be more accurate than others. However, any of the methods will be able to tell whether the car battery is in good condition or not.

Q3: Where Can I Test My Car Battery If I Don’t Want To Do It By Myself?

If you find that the process of testing your car battery is quite intimidating, then you can seek a professional service to help you get this done.

When it comes to testing your car battery and other issues concerning your car battery, then one automotive retailer comes in mind; AutoZone.

This is one of the world’s most renowned automotive retailer that has been in the business for long and has done a recommendable job maintaining its reputation as a top brand.

When you go to AutoZone the car battery testing is done at no charge and this is in any of its outlets in either Mexico, Brazil or any other country out there.


As indicated above, you can test your car battery to know its reliability using several ways.

This helps you know just for how long your car battery can work for your car and if you will have to buy a new one soon.

The car battery in your trunk should be able to meet the power demands of the vehicle when in use.

It is advised that you seek the services of a technician if you find that the process of testing the car battery is rather intimidating.

They might come in handy and even advise on what should be done after examining the car battery.

The technician will also come through if you do not trust the results you get after performing the test on the car battery by yourself.


Written by Kane Dan

My car battery replacement method will help you to swap a battery easily

How To Change A Car Battery

Car battery voltage range is different for every situation of your car status

How Many Volts Is A Car Battery?