Car Battery Load Test With Multimeter | EASY DIY

[@sollykhan2385]

Thank you for posting this video,,shockingly easy ,,,as it 'Empowered me' to do the test's 🙂

[@ReviveMyRide]

Thank you! I’ve found that It’s a good first test if you’ve started having problems and you suspect your battery may be on its way out 👍 cheers, Phil

[@sollykhan2385]

@@ReviveMyRide 🙂

[@Malc2169]

6 * 1.7v = 10.2v, there's your minimum. 6 * 2.35 = 14.1v to 6 * 2.40 = 14.4v while running/charging. That's your numbers. Source - 34 years working in the battery industry.

[@VincentOrosambo]

Do a video mate

[@montanadan2524]

Your cell numbers are good but as we don't know the starter amp draw specifications, his numbers are sufficient for the purpose of the video.

[@Julianpoyopoke]

If my battery went flat every couple of days, I’d replace it without doing any testing

[@lgude]

Yes, excellent video. Easy to follow exactly. The second load test with the min way down was an eye opener. I've certainly heard exactly that kind of weak battery and had enough experience to know it was probably time to replace it. But now I can know for sure. I've got a Fluke similar to yours.

[@ReviveMyRide]

Thank you! Yes, it was an eye opener for me re the second test. I used this info to push a battery supplier into replacing my battery under warranty (although they took a bit of persuading!). Fluke are the best but you pay for it... However, it should last a long time. Thanks for your comment! cheers, Phil

[@I.Live4oldcars.prospecting]

This was very helpful. And easy to understand. Thank you

[@ReviveMyRide]

Cheers! Glad it was helpful! Thanks, Phil

[@I.Live4oldcars.prospecting]

@@ReviveMyRide your welcome

[@Milkybar3320011]

Cold temperatures will also affect the performance

[@ReviveMyRide]

Yes, that’s true! 👍 It’s why so many batteries fail on the cold winter days when we need them most! 🥶

[@bearpuf]

A really nice video. You have a a very fine easy to understand verbal delivery that makes using a multimeter easy for a novice to find out if the battery is good or bad through a load test. Thanks. Good teachers like yourself are worth their weight in gold.

[@ReviveMyRide]

Hi @bearpuf Thanks so much! Glad you enjoyed the vid and it is helping you. 👍 Cheers, Phil

[@nlimchua]

I enjoyed your presentation esp. your accent and enunciation!

[@ReviveMyRide]

Thanks so much! Glad you liked the video 👍I have a kinda weird hybrid accent due to my dual nationality 😁 cheers, Phil

[@BionicRusty]

Another very helpful video. Thank you for posting. 👍

[@ReviveMyRide]

Hi @BionicRusty thanks for your comment, glad you liked it 👍😀 Cheers, Phil

[@montanadan2524]

100% Montana Dan endorsement. The internet contains a lot of misinformation relating to electronics. That is not the case with this video and I strongly agree with the diagnostic approach and the battery voltages specified for lead acid, high output, cranking batteries. Commenters qualifications: I hold a BSEE (Electronics) and have lifelong experience in the mechanical and electronic/electrical fields. My hobbies include a self contained 1989 IP35 sailboat (600w solar 400 Ah AGM, no invertor) and a 2003 Roadtrek camper van (high output self regulated alternator, Victron FET isolator, lead acid start and deep cycle 100AH house, no inverter).

[@ReviveMyRide]

Thanks very much @montanadan2524 👍 Glad to have earned your endorsement on the video, thanks for dropping me the comment!! 😎 cheers, Phil

[@fitzwilly7132]

Not a proper way to do a load test!!! You have no idea how many amps the starter is drawing!! Proper way to test is to use a carbon pile load tester!!!

[@ReviveMyRide]

Thanks for the comment but you have missed the point. This video is for people who don’t have a carbon pile load tester! I’ve done this test lots of times and can confirm that it gives a good indication of battery health. If this test comes back ok and you are still having battery problems, you can start looking in other areas like the alternator not charging properly or your car may have a parasitic battery drain. Thanks, Phil

[@acooper1037]

Nice vid, I think the voltages are specific to your vehicle/battery, one of my cars has an AGM battery which charges at a different rate over (15V DC), on big (generator) engines the control systems are designed to survive 0 volts on start up, with internal capacitors, not sure if cars would utilise the same principals.

[@ReviveMyRide]

Thanks for sharing the info! A lot of my cars have AGM batteries these days. The load test works pretty well on this type of battery for a normal road car. Usually if the voltage drops below about 9.5v during cranking I have found that standard cars often won’t start. Just to add that I agree, charging voltages are getting more complicated, some modern cars vary the charging rate depending on what they have detected the battery condition to be. Some of the more efficient cars, stop charging the battery and the alternator disconnects on an electric clutch if it is full, apparently saves a couple of mpg. Cheers, Phil

[@rosemcbirney5123]

My battery is saying charged 1345 on the bench should it still read that number in the morning if it’s drops down is telling me the battery is failing

[@ReviveMyRide]

Hi, does charged 1347 mean 13.47 volts? Yes, I would expect the battery to have pretty much the same charge in the morning if disconnected and left overnight. If it has dropped a lot, then yes, that wouldn’t be good news for the battery. However, if it stays the same, doesn’t mean the battery is good, hence doing load tests etc to test the battery. Cheers, Phil

[@rosemcbirney5123]

Thank you for responding I will get a load test

[@tammmacdonald7723]

The voltage does not indicate the chargers. Digital multimeters don’t instantly show measurements. In fact the only thing your test shows is that alternator seems to be working properly. However to confirm all the electrical systems need to be switched on and the terminal voltage monitored. Overall this is a poor video.

[@ReviveMyRide]

Thanks for your opinion but sorry, your first sentence doesn’t make sense. I have used this test many times and it does give a good indication of battery health. If the battery can’t maintain a minimum voltage during cranking, it won’t start, usually this means the battery is down on cold cranking amps, this test helps you check this. Also, my Fluke multimeter does show voltage quickly enough to see the minimum voltage, as can be seen in the video. if you are worried about not reading it in time, buy one like mine with a min/max function, it records it! Turning on other electrical systems in the car will be peanuts compared to the draw from the starter motor, therefore it’s not required. Please do me a favour, carry out the test and then come back and comment. Thanks, Phil

[@tammmacdonald7723]

@@ReviveMyRide I can understand why you would think that but just because you have done this many times doesn’t make it right. When you took the first measurement after charging you noted the higher voltage. This is called a surface charge because it is caused by capacitance and an electrostatic charge on the plates. Like any capacitor it decays over time. The only way to know the charge in a lead acid battery is by measuring the specific gravity of the electrolyte. Modern battery testers measure the battery capacitance as the electrolyte also acts as a dielectric that deteriorates as the battery degrades. Multimeters are not instantaneous. Quality ones do read very quickly but they still need time for the A to D converter to sample. There’s plenty of good information on line from manufacturers such as EXIDE, SAFT, CONCORDE. I hope you find this useful.

[@super8forever]

very helpful. thanks

[@ReviveMyRide]

No probs at all! 👍😀

[@wiretamer5710]

I’ve been using a sulphated battery in my Sprinter Van for the past six months. I did so by fitting a cut off switch to the positive terminal of the battery. I keep the battery isolated whenever I know I won't be driving for more than 10 minutes. This also gives me a bit of extra security on the vehicle. The battery has trouble starting the Van if it is left connected for more than 4 hours. The morning start is the hardest. If I can't get it going, I use an emergency jump starter which is cheaper than a new battery in the morning. What I tend to find however is a couple of start attempts, warms up the battery enough to get the car started. After that, normal use of the Van, and continuing to isolate the battery as much as possible, means I don't have any trouble for the rest of the day. All this on a battery I should have replaced six months ago. Next time I buy a new battery I will continue to isolate it and see how long it lasts. For a tiny bit more trouble than normal battery use, I expect a new battery will last at least five years before I have real difficulty.

[@ReviveMyRide]

Hi @wiretamer5710 thank for sharing your experience! Sounds like you are managing the issue pretty well. Yes, it would be interesting to see how long a battery lasts if under zero load when not being used. Cheers, Phil

[@tigermoth3194]

Great video. Now subscribed 👍👍

[@ReviveMyRide]

Thank you! And great to have you as a subscriber 👍😎 cheers, Phil

[@seeyouintheeighties]

mine reads 12.6 and 10.5 during cranking (but not turning over) as my immobiliser seems to keep forgetting key transponder codes and stopping it from turning over and I can't work out why

[@ReviveMyRide]

Hi @seeyouintheeighties sorry, if you can't keep it cranking for a good 5-10 seconds, then you can't perform the test properly. Also, if your immobiliser is playing up, there's a good chance it is the source of your problem. Cheers, Phil

[@fredericksaxton3991]

Thank you for this arcane knowledge. 🙂

[@iansellers406]

Very éducational learned alot thank you

[@ArcanePath360]

My voltage is displayed on my dash on my bike. When I first power up, before cranking, the V sometimes shows it's as low as 6-7v but rapidly rising until it slowly creeps up to 12.2 where I crank it. If I try to start it too soon it dies momentarily and the bike does a factory reset. Usually the 2nd crank it starts up fine.

[@ReviveMyRide]

Very weird symptoms! I haven’t come across that before…

[@ArcanePath360]

@@ReviveMyRide I think there's a big load on it, just as I power it on. It has automatic suspension control which I think it tests as well as a servo motor on the exhaust valve, ABS pump, all kinds of diagnostics I don't even understand. There's a whirring noise which doesn't seem to go away either. I just bought the Topdon BT20 load tester so maybe that will reveal some of what's going on with my starting issues, as sometimes it is a bit iffy at cranking.

[@stevenPounder-p4b]

Batteries especially lead acid don’t have much of a gradual decline in CCA capacity. It’s common to go from starting your vehicle to almost junk when you go for the next start. Simply put end of life is abrupt. It’s just time to replace it. For piece of mind the auto parts store has a load tester to verify the battery. Just personal preference but if you can swing it a AGM style battery is better in every way to a lead acid. With all of that said verify all connections are tight and making proper contact. A weak connection can act like a bad battery or starter ect.

[@geoffhanbury4978]

Apologies for a possibly dumb comment but does removing a lead form a modern car battery (my car is a Skoda Octavia 1.5tsi 2019) cause problems with the car "recognising" the battery when you reconnect?

[@ReviveMyRide]

@geoffhanbury4978 It's actually a very good question! I can't say 100% but I have disconnected the battery on lots of modern cars and never had a problem. A lot of people do it as a basic "ECU reset" from time to time. If I had your car, I wouldn't hesitate to disconnect the battery if I needed to. My latest project car is a 2022 BMW M135i, I disconnected the battery because I'm taking the engine out and I don't expect a problem with it not recognizing the battery when I put it back on. If you search the term "skoda disconnecting battery forum" on google, you will get lots of hits and can do some reading that will help you decide. Hope this helps. Cheers, Phil

[@geoffhanbury4978]

Well @revivemyride? Grateful for a reply.

[@LarryB-inFL]

This is not really a situation to do a load test; if you see a 0.6V drop from full in a few minutes with the car off, then there is either a problem with significant drain on the battery, or the battery is rapidly self-discharging. What you *should* have done is first disconnect the negative lead and check amperage flowing out of the battery with car off. It should be *very* low, I've never measured it but I'd expect less than 200mA. And if it is high, like 1A, then I would expect there is a problem. But more likely, you would see a reasonable number, and all you should do then is leave the battery disconnected and see if it is self -draining. That is common in older lead-acid batteries, as the plates will sulfate and drop that sulfate to the bottom, where it builds up and eventually shorts a cell. If the battery is good, it will barely drop in voltage. Even with a little load on it, you should see it drop to 13.2V, which is the steady state for a full battery (2.2V per cell), before it finally drops and stays at 12V. But if a cell is bad, it will continue to drop, possibly down to 10V (5 times 2V) if one cell is bad, and even lower if the problem is across cells. Also, not sure I would call what you did a "Load Test", but labels may differ across the Atlantic. Here in the USA, a Load Test is putting a measured heavy load on the battery and looking at the current it supplies as well as the voltage the battery can hold up.

[@ReviveMyRide]

Thanks for the very comprehensive comment! I did check the amperage “drain” and it was negligible. I don’t really think it matters what order you do these tests in, it’s more of a process of elimination, usually starting with the most likely and I had a feeling the battery wasn’t holding charge. Maybe I should have included it but I was trying to stay focussed on the load test in this video. My battery is 14 months old and has never been left in a discharged state, so I knew the problem wasn’t sulphate. I’m aware of method for a Full load test using a known heavy load but most people don’t have one of these at home and it’s harder to get to a shop for it to be done if your car is having starting problems. I’ve used this method of using the starter motor as the load many times and have always gotten really good results. Maybe give it a try next time you have a battery issue and see how the tests compare? Thanks, Phil

[@petersimms4982]

🇨🇳👍

[@ralphmowery2898]

When a battery is first taken off charge it will be somewhat higher than the battery will be after it sits a while even if it is disconnected from the car. The battery usually shows about a half a volt higher just after a charge than the normal battery voltage. If the voltage goes below about 12.6 by half a volt then there is a problem. Either a bad battery or a heavy load on the battery.

[@topsmate]

Hello, we have a car starter power product which has powerful features it uses the latest technology sodium batteries strong endurance multifunctional can be used in all kinds of extreme weather we need you to help us send a test video interested in learning more about it?

[@simeunovicm]

You have volt meter on mercedes dash menu in case there is no multimeter around

[@ReviveMyRide]

Good tip! Not sure it will be sensitive enough for a load test but it may at least give you an indication of what is happening with the battery and alternator. 👍 Cheers, Phil

[@susanhenderson2322]

Take battery to a parts store, they will perform a proper load test using the correct tester, your crank till it starts is insufficient time at the minimum disable ignition system and crank for thee recommended time to simulate a longer crank before start.

[@kirkboivin4357]

With that much voltage drop recorded, no further testing is required. It's junk. 😢

[@jonathanwebb8307]

Probably just wants topping up with water. Some of the Varta batteries you can peal off the label and unscrew the caps to top them up. I can see circular outlines on the label so maybe that's the case here. I managed to get a fair few extra years out of mine by topping it up. Unfortunately many if not most are physically sealed to stop owners topping them up.

[@ReviveMyRide]

Hi @jonathanwebb8307 Thanks for sharing, that's a good point! I have topped up batteries before, even made my own distilled water (now that's a video no-one wants to watch!) but didn't on this occasion... Cheers, Phil

[@hap1n355]

I have a upgraded car stereo with amp and if I turn off the engine and leave the light on with radio it will drain my battery with in 5-10 minutes.

[@ReviveMyRide]

@hap1n355 wow, that's quite a battery drain!

[@digger8180]

👍

[@leonardodavinci303]

Nice overview. You didn't put the other promised link in the description.

[@ReviveMyRide]

Thanks! Sorry about the link, totally forgot. I haven't done a video yet on this but there's a channel that I like to watch called "Eric the car guy". He did a good video on this, here's the link! kzbin.info/www/bejne/gXeUmJygn5VmlZI Cheers, Phil

[@petersimms4982]

🇨🇳👍

[@DanWright-w7x]

You can Buy a Digital Battery Analyzer for around $35-$40 that will tell you the State of Charge and the Health of the Battery .

[@ReviveMyRide]

Yes, that’s true. If you’re going to be checking batteries fairly regularly then it would be a good idea to buy one 👍 but for a one off, if you already have a multimeter, then the method in the video is a good option. Cheers, Phil

[@glidezilla]

Brilliant, thanks.

[@ReviveMyRide]

Glad you liked it! 👍😀

[@RobertdeVries-trimaran-sailing]

BS test.

[@ReviveMyRide]

Why do you think so? Just guessing but I imagine you haven’t tried the method shown in the video, maybe didn’t even finish watching it? In short, the method I show works. Measuring voltage drop during a load being applied to the battery is a proven method of checking the condition of the battery. In the video, the multimeter is measuring the voltage and the starter and engine cranking is the load - simples 😁

[@RobertdeVries-trimaran-sailing]

@@ReviveMyRide I think you need to add: acidity test and longer endurance Ah test (3 cars, 1 bike, 2 boats)

[@mushroom4051]

Lol batterys suck

[@ReviveMyRide]

😂👍

[@tonytully5027]

Great video. Correct information presented perfectly 👍👍

[@ReviveMyRide]

@tonytully5027 Thanks very much! 😊 Cheers, Phil

[@WalterSputek]

This is not a proper load test!

[@ReviveMyRide]

Yes, It’s not the test that a garage would do with an industrial style load tester But the method shown in the vid does give a good indication of battery condition. All you need is a multimeter. Could be a useful first step in diagnosing a starting problem. Cheers, Phil

[@davidrobertson5700]

Calculating the battery storage and load voltage gives you a per centage of the battery health. As battery Voltage correlates with how many Amperes is in a battery . An actual load test with a resistor causes heat within the battery which makes its internal resistance value raise. I use the meter method and I am a professional Vehicle Electrician works for me and the many people I teach basic car electrics to. Anyhow, someone who uses a battery tester is incapable of mathematics lol

[@julesviolin]

That cranking sounded really slow rpm to me without even looking at the meter.😅

[@ReviveMyRide]

Agree! You mean the second crank right? First one sounded ok and a lot of people only do one load test. I’ve learned to do two because if you do a short journey, the alternator doesn’t have much time to charge the battery and you can get stranded! Cheer, Phil

[@petersimms4982]

🇨🇳👍

[@steved0603]

Fantastic instructions! Thank you!

[@ReviveMyRide]

Hi @steved0603 you're welcome and thanks for your comment 👍😎 Cheers, Phil

[@mikethompson3534]

Good accurate video

[@ReviveMyRide]

Thank you! ☺️👍

[@cobar5342]

Thank you for a very good video

[@ReviveMyRide]

Thank you! 👍😀

[@bobthrasher8226]

Great idea.

[@ReviveMyRide]

Thanks! ☺️

[@petersimms4982]

Spent 40 years fix German dumpsters , always problems with power drains, spilt drinks,water ingress?? A living nightmare. I’m retired and drive a Tesla mod3 ,never been sooooo happy 😉

[@ReviveMyRide]

I had a Merc CLK for 12yrs, and a BMW Z4 for a similar amount of time, never any issues but the newer cars? Now that’s a different story. I’m glad you are enjoying your Tesla, I’ve been in one, fantastic machines but not my cup of tea 🫖 cheers, Phil