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How to Test Car Battery with Multimeter

Do you know what’s the worst experience you can have with your car?

I’ll tell you. Going on a date, then park your car. You had a good time with your girlfriend. You had lunch together and played arcade games a bit.

Now when it’s time to return you find out, your car’s not starting. I mean if that’s not the worst experience, I don’t know what is.

Who had that experience you may ask? Me, that’s who.

So, having a bad battery can totally ruin your day. But how to know when to change your car battery?

But how long does a car battery last? The answer is 4 years on average. But it depends on many things. So you need to check them on a regular basis to measure their health status.

In this article, I’m going to share a couple of things to help you find out whether your car battery is in good condition or not.

There are a couple of symptoms, that you can observe which indicate your battery has gone rogue.

Your car engine won’t start properly. It will be a struggle to start the engine. Your car headlight won’t work properly.

Battery Sign Check

When you put your keys in and keep it in the run position, you’ll see a battery sign on the dashboard. It means the battery is properly connected. Then when you start your car, the battery sign will go away. Like magic.

If the sign goes away, it means your battery is in good condition. If it stays, it means bad news.

Multimeter Check

So, what you wanna do, is start your car, and let it run for a couple of minutes. Turn on the headlights. If the battery has any surface charge, this will remove that.

Grab yourself a multimeter. Keep the indicator at 20 volts. Also, turn off the headlights.

Touch the red probe at the red (positive) terminal and the black probe at the black point. The black point is the ground. The value should be 12.5 or higher.

If the result is less than that, it means your car battery has gone bad.

But checking only this won’t be sufficient enough. Your car can hold this much energy but when it’s time to start the car, it may not hold up.

So, to check that, you need to start the car. Don’t remove the probes from the battery.

Keep someone looking at the multimeter. Because this will be a 2 man’s job.

When you start the car, the value will reduce. If it reduces to less than 10, then it means the car battery has gone bad. If it’s less than 5 then you should definitely change your battery.

To make sure your car battery is in optimum condition, you can clean the joints. Oftentimes, it gets corroded, dust and debris stuck in the place. You can grab sandpaper and clean with easily. Make sure you’re wearing gloves and protected glasses. After cleaning the joints, just place some WD40 to keep it safe from rusting and corrosion.

It’s really easy to check your car battery, but if you can’t do it you can always take it to your nearest car mechanic. He can check it for you.

Nowadays, people don’t use batteries that run on water anymore, but even if you have one of those ancient batteries, use distilled water to refill the battery.

If you like this article, you can check my other articles on this website.

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