Check Your Car Battery: How to Test With and Without a Multimeter

Check Your Car Battery: How to Test With and Without a Multimeter

Have you ever had to jump-start your car because the battery was drained? If so, you know how important it is to have a fully charged car battery. Unfortunately, many people do not realize this until they are stranded on the side of the road. An excellent way to prevent this is by testing your battery with and without a multimeter. This blog will discuss what each test entails and how often they should be done in order for your car’s electrical system to operate optimally!

You might have a problem with your battery if your car is reluctant to start in the morning. The battery and alternator are the two parts that keep your vehicle running. If one or the other goes bad, then it can be hard to use your air conditioner, radio, power door locks, and windows. The battery is essential because it provides a spark to ignite the gas in order for your engine to start.

Repairs Are Costly, Regardless of the Cause

Try this if you want to know if your car battery is still in good shape. It should last three to five years if you just bought the battery. All batteries will have some differences in lifespan, and a lot of this is because of how you drive if you drive your car in extreme temperatures, either hot or cold, if you do a lot of cross-country driving, or if there are many electronics running in your vehicle. The battery life is not going to be as long as it would be on other cars.

You may know that there is a range for how long your battery will last. It is good to know how to test them when you are having problems. This can either be the cause of your problem or let you focus on another source of the problem.

Using a Multimeter to Test Your Car’s Battery

People often use a device called a multimeter to tell how much power is left in their car battery. The device can measure voltage. It tells how much power is left in your battery. 

Not everyone has a multimeter. But if you want to do car maintenance on your own, you should get one. There are several symptoms that could cause problems with your battery. If you have a multimeter, it will be easier to check if your battery needs to be replaced. A multimeter costs under $15 and is on Amazon. First, turn it on by flipping the switch to using a multimeter. Then connect one of the probes to the positive terminal and the other probe to the negative terminal on your battery. The meter has two scales: volts (left) and ohms (right). Readings in either scale may indicate an issue with your battery which would need replacing immediately.

If it is called a maintenance-free battery, you don’t need to check the acid for your battery. If not, then use a machine to measure the electricity (like how much power is in it).

Step 1: Start by turning your headlights on in your car. Just let it sit for about 2 minutes with the lights on. This will get rid of any charge on the battery. Do not turn the car on to do this; just turn the lights on. You should test a battery after it has been sitting for an hour or more. If you test the battery right away, you might get a false reading because the alternator will still have power left in it.


Step 2: Look at the battery. Ensure there are no white or yellow crusts around the metal terminals. If you see corrosion like that, it will make it hard to read the battery. If this is happening, then we can’t tell if we need to replace your battery. We need to clean the corrosion off the terminals. Use a brush with wire bristles and a terminal cleaner if there’s any corrosion on the terminals. Don’t use soap and water just yet.


Step 3: For measuring voltage, you need to set your multimeter to voltage. The number should be 20 volts. You want to make sure that the number is higher than 15 volts so it can read correctly. Turn off all lights when you measure the voltage. For AC current, don’t use it for this test. We are only measuring DC here.


Step 4: Touch the two probes on the multimeter to the correct terminals on your battery. This means that one probe should be touching a terminal with a minus sign (-) and one with a plus sign (+). The probes are labeled, so you know which is which.


Step 5: Look at the display on your multimeter. A fully-charged battery will measure 12.5 to 12.6 volts, but it will be lower if it is colder outside. If your battery is working at about a 75% charge, you can expect a reading of 12.45 volts. Anything below 12 volts means that the battery isn’t working and has no more charge left.

If the range is between 12.3 and 12.5 volts, you should give your battery a charge.

Step 6: To tell if the battery is broken, turn on the car and see what voltage it has. Usually, it does not go below 10. If your battery goes below 10, then that means it is not producing enough electricity to run your car right.

 If your battery is telling you that there is a problem, then it can be replaced with a new one. If the battery looks like it is working and you measure 12.6 volts on your multimeter, then you should check other sources for the problem in your car. If your alternator tells you there is no power coming out of it, then that might be the issue.


Without a Multimeter, How Can You Test a Car Battery?

The simplest and most efficient approach to check your car battery is with a multimeter. If you don’t have a multimeter, you can try a few things to determine how your battery is functioning. 

Step 1: Something that you can do is look at your battery. Make sure it’s not leaking and that the case is not bulging. Check for corrosion around where the wires are connected if it looks okay.

 Step 2: Turn the headlights on without turning the engine on to begin testing your battery. Leave the lights on for around 15 minutes.

 Step 3: Turn on the lights, start the engine. If the headlights get dimmer or shut off, you have a problem with your car battery. The battery doesn’t generate enough voltage to start your car.

This is not as accurate as using a multimeter. You can’t get specific numbers, but you can see if your battery is working. 

Batteries That Are in Danger of Dying

If you are testing your battery, then you think there is a problem with it. There are lots of signs that will tell you this, so I’m going to mention what they are. First, if there is corrosion on the battery, then it might be time to test it. 

Lights With a Low Intensity

We talked about this in our last test. Dimming lights can be a sign that you need to charge your battery. You will notice it when it is in your headlights and the interior light of your vehicle, too. Other electrical components might not work well, but dim lights are the best sign. 

Starting the Motor Slowly

When your car’s battery is not working the way it should, then your starter motor will not work. The engine won’t turn on. If this often happens you try to start the car, then it means there is a problem with the battery. 


If your car’s battery can’t transmit the current to the starter, you will just hear a series of clicks when starting your vehicle. If this happens, your battery is most likely completely dead, and your car will not start at all. 

Check Engine Light or Battery Light

Indicator lights on your dashboard can be pretty vague. But when the battery is failing, you will see a light that pops up on your dashboard to let you know. Some cars may just give you the check engine light first, while others will provide you with the battery light to tell you about a problem with it. If there are other symptoms like this too, then it’s possible that the battery has a problem and needs to be replaced.

Price of a Car Battery Replacement

If you need a brand new battery, then there are many places where you can get one. The price for a new battery varies depending on the type of car and how much it costs. You can probably find a new battery for around $50-150. There are some batteries that cost $300 or more. But you do not need the most expensive one for your car. You can save money by replacing it yourself rather than going to a mechanic. A lot of people are scared to do work on their vehicles, but replacing the battery is easy. You can find videos with easy instructions.

In Conclusion

 If your car’s problem is electrical, you should test the battery first. If it turns out to be the battery, then you can fix it. But if it turns out to be the alternator, then you will need to fix that too. A multimeter is a good tool for this job. It is worth getting one because they are cheap. If you don’t know how to use one or if you do not have the money for it, then you can go to a mechanic and have him fix your car for you. This will be a lot more expensive than just buying the multimeter. If you have your own multimeter, at least everything would be more accessible next time it breaks down.

Frequently Asked Questions

How do you test if a car battery is good or not?

Connect the multimeter to the negative (-) and positive (+) battery terminals. If you get a voltage of 12.6 volts or higher, your battery is good. Start the car and get a new voltage reading if it drops below 10 when running.

How can I test a car battery without a tester?

If you don’t own a multimeter, you can test if your headlights are working by starting the car and turning on the headlights. If they are dim, it means that the battery is running them and that there is not much voltage coming from the alternator.

What are the signs of a bad battery?

If your car’s battery is dying, it won’t be able to fully power the car. You might notice your headlights are dim or that there is a clicking sound when you start the engine. The battery might need to be pressed on the gas pedal before starting up.

How do you tell if a car battery has a dead cell?

If the battery is not charging to a high enough voltage, this might mean that there is a dead cell in the battery. If it has been fully charged and the voltage is low, this means that it has sulfation. This happens when you use your battery a lot and then recharge it again soon after.