How to Test Your Car Battery with A Multimeter [2022 Complete Guide]

How Many Volts Does a Car Battery

Your engine won’t start. Your lights won’t turn on. The problem? It is most probably the battery! No one wants to be in such a situation, especially when you are in a rush. Unfortunately, these things can confront you at times least expected. One of the best ways to prevent this is to check your battery frequently so that any problem can be resolved before it becomes worse.

If you are thinking of how to test your car battery, read on! This short guide will provide you with valuable insights on the basic knowledge that you need to know. Every novice car owner must know how to diagnose the problem through a series of tests. More importantly, you need to know how to address the issue once it has been identified.

Testing the battery can be done visually, which will give you a hint that there is a problem. Nonetheless, if you want to be sure of your assessment, it will be better to use a handy diagnostic tool that will provide you with an accurate status of how the battery is doing, specifically in terms of its charge.

How Many Volts Does a Car Battery

Physical Inspection of the Battery

To see if the battery is in a good condition, the first thing that you have to do is to open the hood and have the battery physically inspected. A broken terminal, bulge in the case, leaking fluid, discoloration, rupture, and formation of whitish compounds are some of the indications that your battery is no longer in a good state.

During this test, one of the most common problems that you can spot is the swelling or the bloating of the battery case. This can be a result of old age. But, more often than not, the reason for this is that the battery has been subjected to extreme heat, which is why it has been physically deformed. More so, overcharging and internal short circuits can also cause the battery to be swollen.

As you perform the inspection, make sure that the engine is turned off. Allow the engine to cool down for a few minutes before opening the hood. Most importantly wear gloves so that your hand will be protected from anything that you will touch.

Use a Multimeter

If there is one thing that should be always present in your toolbox, it would be a multimeter. It is a handy tool that can be useful in multiple applications, including testing the car battery. This will allow you to test the voltage of the battery and see if it is charged.

For beginners, many will most probably ask how many volts does a car battery need to start? Without the right voltage, the battery will be dead. If an automotive battery is fully charged, at a minimum, it should have 12.6 volts. Once the engine is turned on, the voltage of a charged battery will be anywhere from 13.7 to 14.7.

If you want to test the battery using a multimeter, you should first turn off the engine. Once it has cooled down, remove the positive terminal of the battery and have it cleaned. Connect the positive lead of the multimeter, which is the one that is color red. Attach the negative post to the negative terminal. Check the reading of the multimeter.

If the display shows a value that is lower than 12.4, this is an obvious indication that the battery is in a bad state. You can use a trickle or slow charger to remedy the problem.

How to Test a Car Battery with a Multimeter

Test for Leaks

While a multimeter can be useful for testing the voltage of the battery to know if it is charged, it can also be used for diagnosing a leak. If there is a leak, there will be a build-up of acid on the surface of the battery, which can hinder the latter from achieving its peak performance.

On the voltage scale of the multimeter, set it to low. Touch the negative terminal of the car battery using the black probe. Meanwhile, use the red probe to touch the dirty cover of the battery. If there is a voltage registered in the multimeter, regardless of how small is the amount, this is an indication that the battery started leaking.

Other Signs of Battery Problems

To test the condition of the battery, you need to know the different signs that it is experiencing a problem. The most basic would be when the engine light is blinking. The latter can be indicative of multiple problems in the engine, and the battery is one of them.

Slow cranking of the engine is also indicative of a problem in your battery. After starting the vehicle, if the engine looks sluggish as if it is struggling to start, there is a possibility that you have a faulty battery. This is the case if the engine takes a long time before it finally starts.

Another good way to test the battery to see if there is any problem is to see the fluid level. This should be part of a periodic maintenance. If it is below the recommended level, expect that this will be a precursor of several serious problems.

6 Signs of a Dying Car Battery


In sum, knowing how to test your car battery should be an essential knowledge for everyone. This is going to save you a lot of headache. With a device that is as simple as a multimeter, you will know if the battery is charged or not. To add, with a quick physical inspection, it will be easy to determine if there is a problem that requires immediate solution.

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