How Check a Car Battery

I wanted to begin with providing you all value in a unique way. I have put together a 3 part post for a ‘how-to’ guide for basic car care.

How to Check Your Car Battery and Signals to be Aware of.

Car Battery

Little in life is more frustrating than that moment when you turn the key in your car’s ignition and….nothing happens. What is wrong? Is it the battery? How can you tell?

What many drivers do not realize is that a battery continues to age even when it is not in use. So whether you drive your car frequently or rarely, your battery will typically need to be tested every two to four years and replaced every three to six years.

In this post, learn how to check your car battery to see if it needs replacing. Also learn about early warning signals to be aware of so you can replace your car battery before it dies on you.

Prepare Your Vehicle for Battery Checking

Jumper Cables
If your battery has become covered in debris or corroded, the first thing you need to do is clean it off and inspect it. A clean battery is more likely to last longer than one that is poorly maintained, and sometimes a simple cleaning and inspection can restore weak connections and give your battery new life.

Here is what to do:

– Turn your car off, remove the cover and disconnect the two cables.
– Use baking soda, water and a soft scrub or toothbrush to clean battery acid deposits away from the two battery terminals (positive, negative).
– Blow away any debris with a hair dryer or leaf blower.
– Dry everything with a soft lint-free rag or allow to air dry.
– Reconnect the positive cable and then the negative cable.
– Add a coating of petroleum jelly or auto grease to prevent future corrosion.
– Replace any corroded, frayed or cracked clamps/cables.
– Check the battery casing itself for cracks or excess wear and tear.

After you do this cleaning and visual inspection, you are ready to perform the battery tests.

3 Ways to Check Your Car Battery

Depending on which test(s) you do, you will need a voltmeter or a power probe (you should be able to find each of these at any auto parts store or online).

Method #1Take a Voltmeter Reading.
Touch the positive voltmeter lead to the positive terminal on your car battery while touching the negative voltmeter lead to the negative terminal on your car battery.

The voltmeter will give you a voltage reading. If the reading is lower than 12.4 volts, your battery needs charging. If it is higher than 12.9 volts, your battery is receiving excess charge that needs to be discharged for safety.

Method #2Take a Power Probe Reading.

Jump Start

A power probe is similar to a voltmeter. With the power probe, you want to attach positive to positive and negative to negative on your car battery, exactly the same way you did with the voltmeter. Use Method #1’s voltage readings to determine what to do next.

Method #3Crank the Engine.
The third and final way to check your car battery is by cranking the engine. You may need an assistant to do this test. Turn the key in the ignition and hold it for two seconds.

While you do this, have your assistant hold the power probe as described in Method #2 here. A reading of below 9.6 volts indicates the battery isn’t able to hold the charge.

By knowing how to test your own car battery, you can keep yourself from being stranded when the battery dies suddenly. You can also get your battery serviced when tests indicate to do so and prolong its useful life.


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