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Testing Battery Health in Your Car Truck or SUV

Created on: 2020-05-29

See different ways you can test your vehicle's battery to determine if you need to replace it.

Okay, friends. So, we're in luck. Well, sorta. We have a vehicle sitting outside that seems to be having a frequent issue of starting. And even though we charged the battery and the battery tester says that it's just fine at that 12.4, 12.5 volts like it should be, for some reason, it just doesn't want to start the very next day. Let's figure it out.

Now, I don't know about you, but I get a little bit tired of having to jumpstart or even charge batteries over and over and over just so the thing can just be dead again the next day. There's a couple of things we can do, starting with testing the battery to make sure we at least have a good known battery before we move along to, of course, checking the charging system and even checking for a parasitic draw. Now, we can do this with a few simple tools. We can use a battery analyzer, we can use a refractometer, and, of course, we can use a multimeter. So, let's get back inside and start checking this out. Now, when it comes time to testing your battery, there's multiple tools that you can use. You can use a multimeter such as this. This isn't really going to come in handy when you're testing the internals of the battery, like as in the strength of the battery acid. So, this is great for if you wanted to test voltage, you wanted to see how much that voltage drops when you're actually cranking to see if the battery can hold up to where it's supposed to be voltage-wise. This is great if you have one. Awesome. 1A Auto also sells this right here, which is a battery analyzer. You can just connect it right on here and then go through those screens. It's going to have different modes and it'll tell you about the battery condition. It's charged. It'll also tell you about the alternator and even the starting if you want it to. This is a nice little tool right here. We'll set that aside as well.

Now, let's say you've been charging your battery day after day, and that charger says it's working well. You get in, you start up the vehicle right after you charge it and it starts up and you drive down the road. Awesome. You get to the store, you get out, you go get a little bit of groceries, you come back out and you go to crank it... [vocalization]. "I just charged my battery just a couple hours ago. It should be just fine. What's the problem?" Well, maybe you need a smart charger like this one right here from 1aauto.com. If you were to have this and you plugged it into the wall and you connected it to the battery, it's going to start analyzing your battery for you. It's going to tell you if the internals of the battery are good and they're in good working condition before it even tries charging that battery. The last thing you want to do is try charging a battery that isn't good for charging. So, let's get this out of the way. And that leads us to my favorite tool when it comes time to analyzing batteries. This right here is called a refractometer. If you were to look inside this right here, you're going to see a little chart, and it's going to tell you where the battery charge level is. What we need to do now is you need to make sure that you have eye protection and hand protection. Safety is paramount. After that, we're going to grab a small pry bar or even a screwdriver, and we're going to lift up on these vent covers right here. So, we have our eye protection and our hand protection. The next thing we want to do is remove our negative battery terminal. As I'm looking at the terminals, I can see that there is a little bit of corrosion. Is corrosion good for a battery terminal? No, it isn't. Should you clean it? Yes, you absolutely should. Is this going to necessarily affect the condition of the battery overall? It will over time. And I don't really necessarily think that this is enough that's going to cause the starting issue.

With that said, I'm going to remove the negative battery terminal. I'll set it aside. And now, we're going to open up these vents. I'm just gonna use my small screwdriver here. It's not small enough, but that's okay. Now, when you open these caps, you can see this right along here. This is all the dangerous stuff that you have to worry about. You want to be careful not to get it on your hands. You definitely don't want it to get in your eyes. And, of course, you don't want any sparks or anything like that. So, if you're a cigarette smoker, put it out before you even start this. That's another reason why we removed the negative battery terminal just in case we happen to make a spark of some sort by connecting the battery terminal to a grounding point, okay? So, we know about the dangers. We'll set it right aside. Now, with these caps off, you can see inside the cells. If you had a flashlight, you could take a peek inside there. If you see any chunks of anything floating around in there, it could be from the plates and that, of course, means that your plates are no good inside there. Once you've determined those look like they're okay, you can move along to using this refractometer. The way that we're going to use this is you flip it open like that, and then you're gonna start on one cell and you're going to work your way across, okay? If this cell test good, this cell test good, that cell test bad, good, good, good, your battery is still no good, okay? One cell can ruin your whole battery. So, you need to check them all. I'm just gonna take a little bit of that. This is battery acid in here, so you definitely don't want to get it on your clothes or your skin, in your mouth or anything like that. We're gonna close it up.

Now that we have that on there, you would look right inside here and you're going to see a chart. Down towards the bottom end of that chart, you're going to see something that says recharge. About halfway up, it's going to say fair. And then once you get above that, it's going to say good. As long as it's in the good ranch you're doing all right. If it says fair, well, that's fair. If it's in the recharge, you can try recharging it but more than likely the cell's probably no good. Especially if you go down the line and you find one cell that says recharge and all the rest of them say good, more than likely it's just plain old no good. So, now, it's going to be time to test the next cell. Something that's important to remember about testing these cells is you need to have a clean surface each time you start, okay? I don't want to have some of the battery fluid from this one still on there when I test this one, because I'm not going to get a good reading. You need to clean it down with some water, wipe it down completely, and then retest each cell down the line. Now, if you want to sit through a 20-minute long video, I can show you me testing each one of these cells. You're just going to have to go with the assumption that the cells were all good in exception of just one at this point. Now with that one cell being bad, like I said before, that's going to affect the overall life and condition of the battery. Having just one cell, your car may or may not start right? Today, starts, tomorrow, starts, the next day, doesn't start. Or even, especially if it's super hot outside or super cold outside, it's gonna have a major effect on how that battery condition is and how it actually starts. So, if you have one cell that you noticed was super low in comparison to the others being up high, then you know that you have to replace your battery.

Now, when you're done testing, it's always important to make sure you put these on all the way. If you happen to leave one off at all and moisture seeps its way down inside there, you're going to have a major issue because it's gonna actually contaminate the fluid inside there and it's going to make it so it doesn't have as much charge. Something that's also important to remember is if you're cleaning down this corrosion right along here, a lot of people like to use hot water with some baking soda, right? And you're just going to keep it inside a little cup and you're going to swish it around and then you're going to pour it right over the top, and it's going to eat all this away. It's going to be great. And you're like, "Yes, I fixed it." Problem with that though is that water with baking soda is going to make its way right down along inside here, and then it's going to seep along inside. And if there isn't a good seal on these vents, it's gonna make its way down inside those cells and it's going to contaminate the cell and you could potentially cause major damage to your battery.

Now, when it comes time to cleaning your battery terminals, you can use something as simple as nice hot water. That'll take care of it for the most part. And the rest of it should be done with something like this, a little battery terminal cleaner, okay? So, hot water with nothing special in it. Look at that. No baking soda. It's not going to make its way down in here. I can put all the hot water I want right down along there. It's not going to do anything except come running right out there. That's great. We'll take our little battery cleaner. Give that a couple of spins on there. This is nice and clean and clear. We'll do the same thing to this terminal end. A little bit of hot water. Yeah. That looks good. Take our terminal cleaner. Go around the inside there. That way there, we know we have a great connection. If you don't have one of these, you can go ahead and use one of these little brushes. They're just not as effective. Now, it's time to get our negative terminal back on here. Make sure you tighten it up completely. You don't want to lose terminal, that'll be very bad. Give it a nice wiggle. Of course, we'll check the positive. Give it a wiggle. If it's corroded, clean it down as well. Why not?

So, now, let's say you've tested all those cells and maybe they tested inside that recharge range, but they were all straight along the line. Maybe they were in the fair or even in the good range. That's even better. As long as they're all on the same line, you know you're doing all right. If you're in the recharge, you need to try recharging it and then go from there. Once you're sure you have a known good battery and it's completely charged, at that point, you would want to do either a charging system test to start, and then move along to doing a parasitic draw test, which if you need to know how to do that, you can check out our link below and it will show you how. Now, let's say for some reason you decided not to use safety protection, no hand protection, no eye protection. Maybe you've got a little bit of battery acid in a place that it shouldn't be, maybe on your skin or even in your eyes. You need to make sure that you neutralize that battery acid ASAP. You can do that with something as simple as going to the sink and washing it down with water as much as possible. You want to try to neutralize that acid. As it comes for your eyes, you can, of course, use sink water. It might be a little bit harsh for your eyes. In that case, I would use one of these emergency eyewash stations. Not everybody has one of these though. If that's the case, just like I said, get under the sink, run water as much as you can to try to neutralize that acid. The next thing that you need to do is seek medical attention ASAP.

All right, friends. So, we went over some brief information on how to test your battery to make sure it's in good working condition. I hope that the information was helpful for you. If it was, and maybe you learned something, leave me a comment below. I'd love to hear from you. While you're at it, why don't you smash on that like button if you liked the video, subscribe, and ring the bell? That way there, you could be kept up with all of our latest content. Thanks.

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