How to Test a Car Battery with a Multimeter

You wake up early on a cold morning and have somewhere to rush to! The moment you start your car, you simply hear a chattering sound. What could be the problem? But since you don’t want to guess, you take your multimeter device and begin with checking the car battery if it is fully charged or not.

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Most of the time, when a car fails to start leaving behind a shattering sound, this is a nice indication that you need to charge your car battery. Always ensure that you have the right automotive multimeter device with you so that you can use it whenever needed. In this article, we’re going to teach you how to effectively test the car battery with a multimeter.

First and foremost, you need to have the right tools when checking the battery of your car. The tools that you will need include a digital multimeter device, safety glasses, and protective gloves. These particulars will ensure that you conduct an easy and safe exercise.

Secondly, discover where the battery is located. Most of the car manufacturers around the world place the batteries under the hood. But still, there are those hiding the batteries in strange places that will require checking the car manual for help.

After finding the battery, set up your test equipment. Then, turn the car’s lights and ignition off, and make your items available. Connect the black multimeter test lead to the negative battery and the red one to the positive battery. Change your meter to the dc volts setting. This is the dc reading with the line above it. The dc voltage with the crooked thing is ac voltage. But this isn’t the setting that you want as dc is enough for the battery.

Read the test results. Verify the voltage reading on your display screen. Battery voltage readings maybe as follows: 12.66 = 100% charged, 12.45 = 75% charged, 12.24 = 50% charged, 12.06 = 25% charged, and 11.89 = 0% charged. These readings represent a battery at 80 degrees Fahrenheit. The battery voltage will interchange 0.01 volts for every 10-degree change in temperature.

Understand the results. In case your battery is greater than 12.45 voltages, then it is well charged. If it falls below that, it should be recharged and professionally tested with a device. If your battery is able to hold a charge, then this means that it is good. A bad battery doesn’t hold the charge and it should be charge tested. But this doesn’t mean that if a battery is in low state charge it is bad.

Charge your battery if it has a low state of charge. You can use an alternator or portable battery charger to charge your car battery. When you use an alternator to charge your battery, you will need to jump-start it first. Alternatively, you may be needed to drive the car for 20 minutes or extra at speed not less than 40 mph. Another method of charging the battery is by removing it from your car and charging it at an auto store. This service can be offered at your auto store for free.

Finally, fully test the battery. The moment the battery is in a full charge state, it can be easier to test and see whether the battery is good or bad. Normally, there are two major methods for testing a battery. This is done by use of a loader tester or with an electronic tester. The load tester uses a load on the battery while the tester checks the battery voltage. On the other hand, the electronic tester sends a frequency wave via the battery to show the condition of the cells in the battery.

As you can see, testing the battery is a quick and simple method that can be conducted by any motorist.

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