should i take a battery tester as gospel?

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CarLuver

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i bought one of the small battery tester off of amazon. did all the vehicles i have and one came up replace. its a 2019 honda. its shows SOH at 50% and resistance at 5.7. never had any issue with it starting even in cold weather.

So should i take the recommendation of replace as gospel? not sure how much i can trust the testers
 
i would charge it with a quality charger and retest.

Which small tester off Amazon?

I've gotten opposing results between a Foxwell and a solar...
 
I have a small cheap tester as well, and twice it said replace, both times I took the battery back to walmart and they replaced it under warranty after doing there own test, so I assume mine is working. I understand anything under 60% SOH is going south.

A poor battery will continue to work for a long time if the car is started and run every day. They tend to go south if they sit for a few days - if there bad.

Do you have any other known good batteries around you have tested to just verify the tester has some variance.
 
If you could go into the hospital for a full body scan and they told you the exact age you're going to die, would you?

These battery testers are giving people the willies they previously didn't know they had.

That said, bad batteries drag down alternators, possibly MPGs, and can create odd havoc with the rest of the electrical system.
 
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CarLuver said:
its shows SOH at 50% and resistance at 5.7.
Click to expand...
No idea what SOH or resistance means or how it relates to battery condition. My $300 Midtronics battery tester shows voltage and CCA. It will sometimes say battery is bad if it's discharged or it may say to recharge battery and test again. I can't imagine any tester under $100 is going to give meaningful results.
 
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Had mine in the '16 Nissan checked at AAP a few days ago.. Battery originally had 470 CCA and as I remember it now shows 233 yet the battery tested good and charging it did nothing for the CCA. Research online said 1 CCA per cubic inch of engine displacement is usually sufficient. I'm at just below 2.5 CCA per CI so since I have other cars I can drive if the battery unexpectedly goes south on me I'm going to leave it in the car. If it makes it though the winter I'll have it retested in the spring.
 
FordMan59 said:
Had mine in the '16 Nissan checked at AAP a few days ago.. Battery originally had 470 CCA and as I remember it now shows 233 yet the battery tested good and charging it did nothing for the CCA. Research online said 1 CCA per cubic inch of engine displacement is usually sufficient. I'm at just below 2.5 CCA per CI so since I have other cars I can drive if the battery unexpectedly goes south on me I'm going to leave it in the car. If it makes it though the winter I'll have it retested in the spring.
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A jump box, even a small lithium one, is good for this situation-it gives that little bit extra that will get it going if necessary.
 
It's scientific, i.e. imho theoretical v. practical. I've tested batteries purchased new and they'll have over 900 CCA. Because it's 70F and brand new, though the battery is only rated as 700 CCA. It reminds me of the megapixel conundrum. Everyone thinks 24.3 MP is only ok and 45 is really needed today, when in fact 6 MP with a high quality lense is good enough to do a 8x10 the way we're used to. As it was explained to me, man wants a single number with which to evaluate the goodness of something. Kinda like using premium when a car was designed for regular, 93 is a lot more gooder than 87, so why not treat your car to the gooder gas lol

So in my example, if my battery now read 600 CCA, it would still pass a load test and base the % on 700 CCA, when I know it started at 900 CCA so it's degraded more than indicated. So what does any of this really matter unless as people seem to point out, the car can't start. It's just "good to know" but the data shouldn't be misinterpreted imho.
 
A tester is just a warning to pay attention.

What is your unique situation, how much hardship if you get stranded? Do you drive remote areas with questionable opportunities for a jump start (or don't bother to have jumper cables in vehicle?), have health problems (or passengers do), or drive outside of cell service areas?

Will you lose a million dollar deal or be fired if you are late?

You FAILED to put your location on your profile, leaving us guessing how cold it might get in winter in your region. It makes a difference.

Personally, if none of the above hardships are true, I would wait till it's cranking slower, struggling to start in cold weather. Then again, replacing now is not that much more of a cost per year for batteries.

Long story short, no I don't trust cheap testers. I would rather have a baseline of what the battery voltage was while cranking, then after it has aged, how much has that dropped.
 
CarLuver said:
i bought one of the small battery tester off of amazon. did all the vehicles i have and one came up replace. its a 2019 honda. its shows SOH at 50% and resistance at 5.7. never had any issue with it starting even in cold weather.

So should i take the recommendation of replace as gospel? not sure how much i can trust the testers
Click to expand...

Not sure about the cheap testers, but the midtronics are spot on. If they said replace, the battery was likely to fail the next winter. Of course if you test at the end of winter, you will most often get another summer and fall out of them so the test result seems off.
 
Also, did you input the CCA or CA correctly? Is it a 51R battery in the Honda?

My experience with 51R is that they die suddenly, like they are fine one minute and not the next for whatever reason... I would heed the warning on one of these if it persisted after charging...
 
Marcozi said:
46% of buyers gave it a 5 star rating.
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The little battery testers work great - if you understand what and how they work.

The user enters CCA, and the tester measures resistance, conductance, and voltage - and based on norms its been programmed with based on CCA, can approximate how much battery life if left. They usually flag "replace" at 60%. How accurate is that calculation - probably not great - maybe +/- 5% or so I would guess.

So, what does that 60% mean. Well, it depends on how it got there. If its been dropping slowly every months for years then its likely getting old and can go some more. If it was 80% last month and 60% this month, something internally in the battery is probably gone wrong.

Either way, if your the type of person that just wants your car to start, then they work great and I would heed them.

If your the type that wants every last start out of your battery you can get, even if it means needing a boost some day, then there not for you.
 
Question?
If I take my car to a parts store that offers free battery testing, and they come out to the vehicle to do the test, should the battery be tested while still hooked up to the vehicle or disconnected so that no parasitic drain interferes with the test?
 
i live in western wa where it does not get super cold. car is my daughters and has jumper cables in the trunk. battery is rated at 420 cca and came out the tester at 320 cca .

i will probably head to Costco and pick one up after the holiday as its a mad house there now. 3 year is my experience that honda batteries go belly up anyways
 
CarLuver said:
i bought one of the small battery tester off of amazon. did all the vehicles i have and one came up replace. its a 2019 honda. its shows SOH at 50% and resistance at 5.7. never had any issue with it starting even in cold weather.

So should i take the recommendation of replace as gospel? not sure how much i can trust the testers
Click to expand...
Pull off the vehicle battery clamps and attach the battery tester directly to the battery posts and retest. It's important the battery tester is attached directly to the battery posts.
 
Donald said:
Pull off the vehicle battery clamps and attach the battery tester directly to the battery posts and retest. It's important the battery tester is attached directly to the battery posts.
Click to expand...
Mine asks me whether I am testing in the vehicle or out. What it does with that info I have no idea. I agree its likely more accurate out - but at least they have thought about that problem.
 
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