[Highbob]

Hello,

My Highlander (2015) got a battery warning light this week (turned on for a moment and then went off, again and again for about 30 min. The next day it did not appear). I bought a battery tester and tested the battery which I bought on Dec. 2021. The test result shows that the battery needed to be replaced. The follow are the test result data:

State of Health = 53%
State of Charge = 100%
Test Value = 512CCA
Battery Voltage = 12.63V
Internal resistance = 5.80 mOhm
Test Result = Need to be replaced


I went to the shop where I bought the battery and got a replacement (same battery, brand new).
Before I install the new battery in my car, I tested it out-side of car. The results are:

State of Health = 70%
State of Charge = 100%
Test Value = 584CCA
Battery Voltage = 12.70V
Internal resistance = 5.10 mOhm
Test Result = Need to be replaced

I was wondering why a brand new battery needs to be replaced. I thought may be I had to give it a charge. I did not return / change the battery at the store immediately.

Today, I drove my car for about 2 hours on highway (about 80 miles). After 2 hours I stopped driving, I tested the battery again. The results are:

State of Health = 71%
State of Charge = 100%
Test Value = 589CCA
Battery Voltage = 12.82V
Internal resistance = 5.10 mOhm
Test Result = Need to be replaced

My question is: Are the test results true? Why a brand new battery need to be replaced? Which item in the test result data is bad? Do I need to return/replace the new battery I got yesterday?

Thanks for any advise.

Bob

 

[JohnGD]

Battery light means the battery is being discharged. And when the car's running that may indicate an alternator or wiring (loose or corroded) problem.

The voltages 12.63 and 12.82v actually looked pretty good to me. When I get a new battery I'd put it on a charger. You might also want to let a parts store do a charge and battery test. They can also test your charging system. I'd think you need to enter the relevant battery information before it'll give you accurate results.

What's the voltage when cranking? More than 10v? And the voltage when the engine is running? Generally you should see around 13.5-14.5v.

 

[toatgoat]

What does your battery tester say about the batteries in you other vehicles?

 

[NameofUser]

+1 all NEW batteries should be fully recharged before placed into service. It may have sat on the parts shelf for awhile becoming discharged.

Is this battery tester a load tester? That is the most meaningful measurement for a 12V batt, that has a traditional starter.

What is the voltage output at the 12V+ battery terminal when the engine is running? It should be >13V+.

Are the battery cable terminals tight and clean? Is the negative cable (not at the batt terminal, butnat ground connection) tight and clean?

 

[katekebo]

It looks like there could be a problem with your alternator / charging circuit. Even a new battery will test poorly if it is not being charged properly by the alternator.
Do the following test.

• Measure the battery voltage with no load (key out of ignition). It should be somewhere around 12.6 to 12.8 V
• Start the engine and measure the voltage immediately afterwards. It should be somewhere between 14.0 and 14.5 V
• Continue monitoring the voltage. After a short time (minutes) it should drop to about 13.8 V. If the voltage stays above 14 V for a long time, your charging circuit is overcharging your battery and it will shorten its life. If the voltage stays below 13.8 V, your charging circuit isn't fully charging your battery and it won't reach 100% charge.

 

[Highbob]

Thank you every one. Your advises are very helpful for me.

Maybe the battery's problem is coming from I didn't give it a full charge before start to use. I did not know it. I will do it next time.

I will upload some photos and video tomorrow to show the test results and the car battery warning light.

Bob

 

[Highbob]

Battery light means the battery is being discharged. And when the car's running that may indicate an alternator or wiring (loose or corroded) problem.

The voltages 12.63 and 12.82v actually looked pretty good to me. When I get a new battery I'd put it on a charger. You might also want to let a parts store do a charge and battery test. They can also test your charging system. I'd think you need to enter the relevant battery information before it'll give you accurate results.

What's the voltage when cranking? More than 10v? And the voltage when the engine is running? Generally you should see around 13.5-14.5v.

Good morning JohnGD,

At first, I was also thinking the alternator was broken. I bought the battery tester and did charging tests. Here are the results.

(1) Old battery : had the battery warning light on and off. used for about 16 months. returned.

(2) New battery : just installed before drive

(3) New battery: after 2 hours highway drive

All the test results say it is normal. I also have a battery voltage monitor inserted in the 12V socket in the car, and I can see the voltage is between 13.8V to 14.2V and 0.2A to 1.5A when driving .

I did cranking tests too. The following are cranking test results.
(1) Old battery

(2) New battery : after 2 hours highway drive

I have a question. Do I need to remove the new battery and do a full charge using a battery charger now, even I can drive my car without any problem now?

Thanks.

Bob

 

[Highbob]

What does your battery tester say about the batteries in you other vehicles?

Good morning toatgoat,

I did a test with the battery tester on another car's battery (RAV4 2007). It says the battery is in Good condition.
Here is the test result.

 

[Highbob]

+1 all NEW batteries should be fully recharged before placed into service. It may have sat on the parts shelf for awhile becoming discharged.

Is this battery tester a load tester? That is the most meaningful measurement for a 12V batt, that has a traditional starter.

What is the voltage output at the 12V+ battery terminal when the engine is running? It should be >13V+.

Are the battery cable terminals tight and clean? Is the negative cable (not at the batt terminal, butnat ground connection) tight and clean?

Good morning NameofUser,

The battery tester I bought does have load tests for charging test.

I think the cables are tight and clean. I don't know the negative cable is grounded or not not at the battery terminal. I will have a check today.

Thank you for your advise.

Bob

 

[Highbob]

It looks like there could be a problem with your alternator / charging circuit. Even a new battery will test poorly if it is not being charged properly by the alternator.
Do the following test.

• Measure the battery voltage with no load (key out of ignition). It should be somewhere around 12.6 to 12.8 V
• Start the engine and measure the voltage immediately afterwards. It should be somewhere between 14.0 and 14.5 V
• Continue monitoring the voltage. After a short time (minutes) it should drop to about 13.8 V. If the voltage stays above 14 V for a long time, your charging circuit is overcharging your battery and it will shorten its life. If the voltage stays below 13.8 V, your charging circuit isn't fully charging your battery and it won't reach 100% charge.

Good morning katekebo,

Thank you for your advise and instructions.

I believe my car's alternator doing overcharging because I had a battery problem with the original OEM battery came with the new car when I bought it. There came a lot of white and green powder on the plus terminal. Someone told me that it was because the battery was overcharged. But that battery lasted about 6 years and 160,000 miles.

Is there a method to reduce the charging voltage of the alternator?

Thanks.

Bob

 

[CamPoo]

So which of the tests shows the voltage first thing in the morning, before first attempt to start and without any charger hooked up overnight?

My 'new' batteries when charged fully will sit overnight and show 13.2-13.3 in the am.

 

[Highbob]

This is my test equipments.

 

[kenny-bob]

At first i thought maybe the old battery was still good and could be charged up and used for additional service, and i was gonna say you need to get a new battery Tester, since it failed out the new batteries.

But after seeing that picture of the corroded terminal, i don't think it's possible to make any decisions about batteries, testers or alternators. Such is the life of a neglected starter battery, expected to perform under all conditions...

And now after seeing the so-called battery analyzer, i think it is a joke. To test CCA requires a high load for 30 seconds--no way that little thing can absorb that much energy. It's cool that it can talk to the phone app though.

 

[NameofUser]

I believe my car's alternator doing overcharging because I had a battery problem with the original OEM battery came with the new car when I bought it. There came a lot of white and green powder on the plus terminal. Someone told me that it was because the battery was overcharged.

You and this other person don't know why battery corrosion occurs.

Read and Learn:

How to Clean Battery Corrosion (and What Causes It) | Continental Battery Systems

How to Clean Battery Corrosion (and What Causes It) | Battery corrosion is something vehicle owners have had to deal with. See our suggestions on how to clean battery corrosion and what causes it in the first place

www.continentalbattery.com

 

[NameofUser]

+1 on the "high tech" battery tester. Sure the info displayed is nice & neat, BUT, as @kenny-bob said, that toy unlikely able to handle a simulated starting load (say 100Amps) = a lot of heat to absorb and dissipate.

You can see old school analog load testers for sale on HomeDespot, WrongMart, Amazon. Notice the size and it is a vented metal box. VENTED for a very good reason. Absorbing electricity for the load test results in heat.

I would return that 12V battery tester toy. Go buy a quality Digital Volt Meter from Amazon, HomeDespot, Lowe's. A usefult tool for the car and home.

You can always goto your auto parts store and to have a load test performed, as they will be happy to sell you a new 12V batt. OR you can buy a true load tester. HorrorFreight (Harbor Freight) even sells one for $22.

FYI, Hybrids, PHEV, and EVs don't have a traditional starter that "turns" an engine. The 12V batt, in hybrids and PHEV, power the computers, and the computers tell the high voltage battery to suipply high voltage to spin-up the engine, not w/ a traditional starter, but from within the transaxle (think transmission). A load tester on a 12V batt in these cars will produce a lot of false positives.

 

[NameofUser]

Is there a method to reduce the charging voltage of the alternator?

No.

 

[NameofUser]

I think the cables are tight and clean. I don't know the negative cable is grounded or not not at the battery terminal. I will have a check today.

Some of the automotive aspects might beyond your skill set.

If the negative cable was NOT grounded, you would have far worse problems, like nothing working/starting.

You would want to trace the negative cable from the negative battery post to where it finally ends somewhere in the engine compartment. You want to make sure this connection is indeed connected and tight. If loose, tighten. In the off change it has corrosion or is just not "clean", then clean it up.

You could also do the same for the positive connection, except it will lead back to the alternator. Same concept and concern: are the connections clean and tight? The wire is intact (no cuts or break in the wire insulation). A loose and/or unclean connection can cause problems.

Good luck.

 

[Pefi]

... now after seeing the so-called battery analyzer, i think it is a joke. To test CCA requires a high load for 30 seconds--no way that little thing can absorb that much energy. It's cool that it can talk to the phone app though.

Such small battery testers can use several different principles to guesstimate the state of a battery:
1. Battery can be loaded with some small yet significant DC current (e.g 10A) for a very short time (e.g. 10 ms). This way the internal resistance can be measured and even such small device can handle that amount of heat quite easily.
2. Tester might load the battery with quite small AC current and there is a indirect method how to estimate internal DC resistance from small AC current.
3. Testers measure voltage drop when the car is cranking and it is known that the DC voltage must not drop below approx 9.6 volts.

I guess the battery tester on the photograph is using method 1 (to measure internal resistance) and method 3 (to show the voltage drop). Result from the method 1 can be used to guesstimate the CCA.

Such device is very useful as long as you perform the diagnostics first when the battery is new and from there you can monitor the degradation (increas of internal resistance) over time. Such device is quite useful as it can warn you that the voltage drops too much while cranking and there is a risk the car might not be able to start once there is cold outside.

Anyway the measurtement results (resistance, CCA, voltage drop) are highly dependent on temperature! You cannot compare results obtaind at significantly different temperatures unless the device performs temperature compensation.

Too big voltage drop for a new battery may be caused noty only by a faulty battery, it may be indication of wrong battery type for a given vehicle, or indication that the cranking requires unusually high currects (e.g. wrong oil visocity for given cold climate). It may be also observed also when the temperatures are really low and the battery is really cold.

For normal (ie. room) temperatures) and fully charged battery the manual for a small CTEK charger/tester (CTEK MXS 5.0 Test&Charge) provides the following cranking voltage tresholds:
Above 10.5V - good
9.6 - 10.5V - acceptable
below 9.6V - bad

 

[kenny-bob]

Such device is very useful as long as you perform the diagnostics first when the battery is new

The OP did use it on 2 new batteries; it gave the same result as for the old battery, namely to replace them.

How much confidence could the average person be expected to have in such a device with test results/recommendations such as this on NEW batteries?

Maybe a 10 msec test could guess about something? What is the inductance and resistance of the load, and of a starter motor?

 

[gsfent]

Two hours of highway driving should be enough to top of a battery, even if running a bunch of appliances (AC and headlights are the big consumers).

If the OP doesn't already have one, get a good smart battery maintainer/charger. I have a one from Harbor Freight (goes on sale regularly for about $40-50). Can do slow charge, medium charge and operate as a jumper pack. Choice of normal or AGM batteries.

Put it on the new battery and let it charge for a day or two to "top it off". Once topped off, check the state of health over time. If it declines, then you either have a battery that sat around for a long time on a shelf (manufacture date usually as a sticker on the battery) or there is a small internal issue OR your charging system is not up to snuff.

Alternators today have a built in voltage regulator, so if bad, generally you replace the alternator and not just the VR. If the VR is a separate unit, you can look into replacing that if charging voltage is low.

If it is not maintenance free, then check the level of the water (with car off!). Top up as necessary to cover the plates. If maintenance free, then there is no access.

Regards,
Jerry