The Pro Guide to Testing Your Car Battery

A car battery is a critical component in your vehicle. Without it, you can’t start the engine, and you’ll be stuck on the side of the road. It’s essential to test your battery regularly so that you know when it needs to be replaced before something goes wrong. In this blog post, we’ll discuss how you can perform basic tests at home with minimal equipment to check if your battery is working correctly or not.

The battery is like your car’s heart. Without it, the car won’t work. The battery has to work well for the vehicle to do well too. Your car won’t start if the battery malfunctions. You should check the battery to see if it is okay. Make sure to take care of your car’s electrical system, too. Here is how you can test the battery of your car like a pro.

Take a Load Test

Doing a DIY test on your car sounds like it is hard. But you can check the battery without any technical expertise. Here are the steps:

  • You should turn on the headlights while the engine is off.
  • Turn on the light for 10 minutes or so.
  • After that, start the engine. Stand outside of the car and look at how bright the headlights are.

If the car’s headlights dim when the engine starts, it means that your battery is not working. A good battery should be able to keep going for 10-15 minutes if you have a dead battery. If you notice that it is struggling, change it before it fails in the middle of nowhere.

Make use of a multimeter

A car battery has electricity in it. A multimeter is used to check the level of the electricity inside the battery.

  • A multimeter can tell you if your battery is okay. Use the multimeter to test if your battery has enough power to start your car. First, set the meter for DC voltage, then touch the black probe with the battery’s negative terminal, then the red probe with the positive terminal. If you turn on your car’s headlights, it will give a light load to the battery. Check the reading on the voltmeter when it is 26C (80F).
  • If you have a reading of 12.5V or more, this means your car battery is working well.
  • If the voltmeter reads 12.3V, it suggests that the battery is roughly 75 percent charged.
  • If your battery’s voltage is below 11.8V, it means it has less than a 25% charge.

When you get a low voltmeter reading, charge your car battery for a long time to make it work better. If the readings do not change, your battery is about to die and needs to be replaced.

Check Car Battery With a Load Tester

Going on best car battery testers reviews and buying guides is an excellent thing to do when your car doesn’t have enough power. You can figure out if you need a new battery or not by reading reviews and guides. Most dealerships use load testers on batteries to see if they are good or bad.

When you use a load tester, it puts electricity on the battery. The tester checks the voltage. If the voltage is under 9.6V, then your battery needs to be replaced. You can also use an electronic tester that sends waves through the battery to see if its cells are good or not.

The Gravity Test of Electrolytes

You can test the car battery from home using a hydrometer. The electrolyte gravity test helps you to see if the battery is charged or not. It is better to use a hydrometer that has a thermometer in it.

Most hydrometers adjust themselves. But some need to be changed based on the room temperature. Wear goggles and gloves when testing the electrolyte gravity. Do this by following these steps:

  • Take the tops off your batteries.
  • Before releasing the hydrometer bulb, dip the end of the hydrometer into the battery’s first cell.
  • Release the bulb gently so that the electrolyte can flow into the hydrometer needle.
  • Before redoing the test on the other cells, note down the electrolyte-specific reading for the first cell.
  • Compare your findings to those recommended by the battery tester’s instructions.

If your hydrometer readings are between 1.265 and 1.299, then your car battery is fully charged. If it is below that, then your car battery needs more charge. You can get a trickle or slow charge to help you restore the charge in the battery and improve the chemical reaction in the battery too. But if there is a difference of 25 to 50 points (1 point equals 0.001) between two readings, then your car needs to be replaced because it has sulfated batteries inside of it.

Bottom Line

Testing a car battery from the comfort of your home can be simple and inexpensive. It also teaches you things. When you think the battery is not working, choose any of these tests to find out what is wrong with it.

Frequently Asked Questions about How to Test Your Car Battery

How to know if your car battery needs replacing?

A car battery is like a cell phone charger. It can get worn out and stop working if it’s not used regularly. A slow engine, dim lights, electrical issues, the check engine light on, a bad smell, or corroded connectors are all signs of a dying battery. If your battery seems old or misshapen, you should replace it with a new one.

When testing a car battery what should it read?

You should check the reading on your car battery. If you see 12.6-12.8, then it is in good shape. It is best to read any voltmeter between 12.4 and 12.9 volts because anything higher than that means there is a problem with your battery, and it needs to be fixed right away!

What setting should my multimeter be on for a car battery?

To test the electrical output from a vehicle battery, you should turn on the dial to the “20 volts” setting.

Is 14 volts good for a car battery?

The car needs to read 12.6 volts when it is turned off. If the voltmeter reads about 14-15 volts, then the battery is normal, but if it reads more than 15 volts or less than 13 volts, then there might be a problem with the voltage regulator, wiring, or alternator.

How can you tell if a battery is good or bad?

If you think your battery is bad, you can see for yourself. Take a look at the terminal, if it’s broken or loose. If there is a bulge or bump in the case, it might be bad. You can also check if there is a crack or rupture in the case and whether there’s too much leaking from an old battery. If your battery has discolored patches on it, this could be a sign that it needs to be replaced.

What are the signs of a bad battery?

When your car battery is failing, it can’t give enough power to your car. This means that things like the headlights will be less bright. It also means that you’ll have problems starting the engine, and it will make a clicking sound when you turn the key. And sometimes, it’ll backfire while driving or when you try to start the engine.

What voltage should my battery idle?

A charging system that is usually working should produce roughly 13.8 to 14.3 or more volts at idle. If the charging voltage does not meet 13.0 volts, the alternator is not sending out enough volts and current to keep the battery charged.

At what voltage is a car battery dead?

11.9 volts is the voltage of a fully charged battery. If it is less, then it should be recharged.

What voltage should a 12 volt battery read when fully charged?

If you have 12.6 volts or more, then your battery is healthy. If it goes down to 12.5 volts, then your battery may be dying, and you should check again in a few days to see if the voltage has gone down more.

What do I set my multimeter to for 12V?

You need to set the multimeter set to measure the voltage of something. If you are measuring a 12V battery, then use the 20V setting.

What is the voltage of a dead 12-volt battery?

On a battery that is resting, the voltage should be around 12.8 volts. If the battery is fully charged, then it will be at about 12.9 volts. When a battery is dead or flat, it will be at 12 volts. So if your battery reads 12.4 volts, then it means that it’s about 50% charged.

Are 11.6 volts enough to start a car?

The standard voltage to start a car is 12.6 volts. When exploited, this parameter was between 13.7 and 14.7 volts.

To learn more information about testing car batteries with a multimeter, click here.