It is very cold, how do I know if the car battery is good and the car will start?? What is the best car battery test method?

[Don2222]

Hello
Nowadays there are better tools to get and know how to use! The old standby was the 5 year old premium Sears Die Hard. They are still sold by Advanced Auto but the warranty is 3 years. Our Toyota Venza has one with the date code of 01/22/2021 and will not start in this wether with temps down to 15.4 at night and about 20 degrees F in the morning. The doors unlocked, the dashboard lights lit but not enough cranking Amos to start the car! A jump from another car and it did get going very easily. Also this car is not used every day so that can also contribute to this issue.
Now the RAV4 has an Exide Excel battery that is 4 years old and still starts well unless the dome light is left on all night.
Now testing the car alternator is fairly simple. When the car is running just put a multi-meter on the battery and a voltage reading of approximately 14 VDC indicates the 12 volt battery is getting charged with the higher voltage. If the voltage is not higher that the 12 volt battery then the alternator is bad,
So how do we know if the battery itself is good under a load?
There is a very good vehicle battery tester at Batteries Plus & Bulbs for $44.95 that puts a load on the battery and has a simple to read meter result!
Just attach the battery clamps and depress the momentary rocker switch to load the battery and read the results!
The proof is how it really works so here is what I found.
The Exide Excel battery that is 4 years old when the load button was depressed showed 11 volts and just bearly in the yellow weak area on the top scale.
Just to be safe with the start of this big cold spell I replaced it with a premium high performance X2 I asked why this battery is better than the premium Duracell. They said the Duracell uses recycled lead and the X2 uses pure lead and will last longer than 5 years. After installing the X2 I tested it. Sure enough the results on the 800 CCA Cold Cranking Amp scale for this 840 CCA battery are well in the green after the load button was pressed.
Now what will the DieHard with 650 CCA Venza battery test at??
Looks like the Venza battery with the needle way down in the Red needs to be replaced?
Pic 1 - Batteries Plus - New Auto Battery tester
Pic 2 - Basic Instructions for the Tester
Pic 3-5 New Premium High Performance X2 battery from Batteries Plus
Pic 6 - RAV4 Battery Voltage with just the leads attached with new X2 Battery Installed
Pic 7 - RAV4 Battery Voltage with load button depressed with new X2 Battery Installed
Pic 8 - Venza Battery Voltage with just the leads attached on 3 year old Diehard
Pic 9 - Venza Battery Voltage with load button depressed on 3 year old Diehard

 

[johneh]

Don what you did was what mechanics have been doing since the lead acid battery was invented
A Carbin Pile Test. I am 75 and my tester belonged to my Father in law who was also a mechanic
in the 1940s Same machine just a new look LOL

 

[bigealta]

Just get the digital volt readout that goes in the cigarette lighter. Easy to watch the voltage at startup and when driving. They are super inexpensive.

Obviously it won't do a load test, but you will notice changes in normal voltage readings over time if your battery or alternator starts to fade.

 

[weee123]

In the wrench turning business we called those load testers toasters

 

[Don2222]

A lead acid battery carbon pile test with a toaster!! - That is why this meter Smokes the first time you use it! It states that in the instructions! LOL
Good to Know Thank-You

 

[Murray01]

Why would one shop pass a load test on a brand new AGM battery and a second shop fail a load test claiming one cell is dead? Battery was dated Nov 23 so it sat on a shelf for a year. Said battery was not charged before installation.

 

[Whitenuckler]

Ancel BM200 Bluetooth Battery Monitor

Just installed this today. I am having issues with my Jeep.
I wanted a wifi one, but they are harder to find and more expensive.
I can't get the bluetooth in the house very well, but can in the porch.
The app seems good. It is able to record the crank cycle ie voltage verses time.
Also has a charging test you can run with the car running.
I have a trickle charger on it now so I can make sure it's charging remotely.

 

[johneh]

The old standby to test a car battery is a carbin pile load test
This is what mechanics have used for 75 years. If you have the
battery tested at a parts store or your local shop, that is what they will use
On my plow truck, which is used infrequently, I have a Battery maintainer
which keeps the battery fully charged when not in use, also have one on
My portable genny and the whole house generator

 

[Whitenuckler]

The old standby to test a car battery is a carbin pile load test
This is what mechanics have used for 75 years. If you have the
battery tested at a parts store or your local shop, that is what they will use
On my plow truck, which is used infrequently, I have a Battery maintainer
which keeps the battery fully charged when not in use, also have one on
My portable genny and the whole house generator

Yes, that is a real test, the one that draws lots of amps. I have a "battery Tester", which is the size of a meter, and it can measure the cold cranking amps. It does give you an idea of the health, but you can't duplicate real amps. That may be one good thing about this monitor. When you do a crank test, the battery is outputting it's starting amps, and the monitor looks at the terminal voltage. A good battery will keep the volts up above a certain level, a bad one (possibly mine) the volts will be too low. I mostly hooked it up to monitormy trickle charger which is plugged into a GFCI on the side of my garage. One day after some wet weather it tripped, but I didn't know. It is also feeding my heated bird bath. My first clue was when the bird was walking on the bird bath.

 

[EatenByLimestone]

I just turn the key. It’ll either turn over and fire or it won’t.

I actually picked up a new battery a couple days ago as it started slow a couple times and the battery is from ‘18. I had it in my back seat. Since it’s going to be -3 or so tonight, I brought it inside to stay warm. I really should install it, lol.

 

[Whitenuckler]

I just turn the key. It’ll either turn over and fire or it won’t.

I actually picked up a new battery a couple days ago as it started slow a couple times and the battery is from ‘18. I had it in my back seat. Since it’s going to be -3 or so tonight, I brought it inside to stay warm. I really should install it, lol.

I replaced my 2012 vintage AGM with a new one this year, but I suspect the new one is bad. When it arrived it only had 10V on it.
I also suspect some parasitic draw, because it was hard to start. That's hard to find, so I just put the trickle charger on for now. I thought I'd have this all figured out by now, but I guess not. Good thing I'm not going anywhere.

 

[begreen]

Methinks the new lead vs recycled lead story is blowing smoke. What generally makes a lead acid battery last longer is the quality of construction (separators, etc.) and the thickness of the plates, and of course its treatment in use. The battery in our Dodge van is into its 7th year. That's a good battery.

"The lead from lead batteries can be infinitely recycled with no loss of performance and nearly 70% of the lead used in a battery comes from recycling."

New study reveals lead batteries are the most recycled product in the U.S. with a 99% recycling rate – ILA

ila-lead.org

 

[EatenByLimestone]

I imagine there’s lots of parasitic draws on a vehicle now. All those computers need to be on standby. Can’t have them completely cold start and relearn everything on every startup!

 

[Whitenuckler]

I imagine there’s lots of parasitic draws on a vehicle now. All those computers need to be on standby. Can’t have them completely cold start and relearn everything on every startup!

This Jeep has every gadget going - I don't know how many computer modules it may have.
I would need to break the negative on the battery and hook a meter in to see, but that will be a spring job.
Well the BM200 paid for itself last night. I went to the porch to update the app, and I can clearly see
that trickle charger under the hood is not working the way it should. I will try another one as I have
a couple of others that are the same. I did notice one of the indicator lights didn't work, so maybe it's damaged.

 

[Murray01]

This Jeep has every gadget going - I don't know how many computer modules it may have.
I would need to break the negative on the battery and hook a meter in to see, but that will be a spring job.
Well the BM200 paid for itself last night. I went to the porch to update the app, and I can clearly see
that trickle charger under the hood is not working the way it should. I will try another one as I have
a couple of others that are the same. I did notice one of the indicator lights didn't work, so maybe it's damaged.

Your Jeep may have 2 batteries. To my understanding if your Jeep has the Auto off/auto start feature then you’ll have 2 batteries. One is obvious, the other is hidden under the main battery or hidden elsewhere. If you have 2 negative leads on your main battery then you have 2 batteries. It is recommended to replace both. This is what I have researched on Jeep Wrangler forums and FB Jeep groups.

A trickle charger may not supply enough amps to charge both batteries, kind of like peeing in the ocean.

What I do is measure the voltage in the battery then put the battery on charge and re meaure the voltage, should be reading 13-14.5 volts thanks to the charger. Get the vehicle running, disconnect the charger(or booster cables) and measure the voltage again with the volt/ohm meter, again should be up in the 13-14.5 volts thanks to the alternator, if it’s not then your alternator could be shot.

A load test should be done on a freshly charged battery. If you buy a new battery, before you leave the store have the counter attendant do a load test on the new battery. Too often the new batteries have been sitting in a warehouse and are never charged since coming from the factory.

If I get 3 winters out of a battery on a little used F150 I’m not happy but that’s life living in a cold climate.

 

[Whitenuckler]

Your Jeep may have 2 batteries. To my understanding if your Jeep has the Auto off/auto start feature then you’ll have 2 batteries. One is obvious, the other is hidden under the main battery or hidden elsewhere. If you have 2 negative leads on your main battery then you have 2 batteries. It is recommended to replace both. This is what I have researched on Jeep Wrangler forums and FB Jeep groups.

A trickle charger may not supply enough amps to charge both batteries, kind of like peeing in the ocean.

What I do is measure the voltage in the battery then put the battery on charge and re meaure the voltage, should be reading 13-14.5 volts thanks to the charger. Get the vehicle running, disconnect the charger(or booster cables) and measure the voltage again with the volt/ohm meter, again should be up in the 13-14.5 volts thanks to the alternator, if it’s not then your alternator could be shot.

A load test should be done on a freshly charged battery. If you buy a new battery, before you leave the store have the counter attendant do a load test on the new battery. Too often the new batteries have been sitting in a warehouse and are never charged since coming from the factory.

If I get 3 winters out of a battery on a little used F150 I’m not happy but that’s life living in a cold climate.

I don't have auto start except through the remote (which stopped working again after a new FOB).There is a chip key you have to put in and turn. I took a look at my battery pic and it appears to just have one neg.
Was just out and it was very cold with the wind chill. I opened the hood and the stupid charge was off. I think it's bad. I put another on that I know is good, and put the "bad" one on the battery the "good" one was on so I can watch it. Soon I will get another bluetooth data download.
The alternator is good. I have a USB plug that goes into the 12V socket and it reads volts. My alternator is fairly new too as it was replaced under warranty. The BM200 has a test for that too, but I have not tried that.
re Buying batteries. I ordered this replacement AGM from Amazon - And I know they shipped an undercharged one, but it is hard to return. I managed to get it working OK...of course if I have a parasitic draw, and a bad charger, then it may not be the battery.
If I end up buying a new battery at Canadian Tire (I have a sale alert on it), I am bringing my meters with me. Of course it wouldbe much easier to get a replacement from a local store. It's a bit of a PITA to pull it as it's under the passenger seat.

 

[Whitenuckler]

This Jeep has every gadget going - I don't know how many computer modules it may have.
I would need to break the negative on the battery and hook a meter in to see, but that will be a spring job.
Well the BM200 paid for itself last night. I went to the porch to update the app, and I can clearly see
that trickle charger under the hood is not working the way it should. I will try another one as I have
a couple of others that are the same. I did notice one of the indicator lights didn't work, so maybe it's damaged.

Replaced the charger and back in business. I wonder if the chargers don't like to be left connected? I have it under the hood, and the extension cord hangs out in front of my hood. When I want to go for a drive, I just unplug the AC cord. It should not matter but that is the only thing I can think of. It has three modes and a light for each. I had noticed that one of the lights didn't work. Maybe it got zapped.

 

[Murray01]

I’m not convinced that AGM batteries are the answer for all vehicles.

Had an issue last winter, purchased a AGM which was NFG from the get go. One shop claimed the new battery passed a load test therefore you might need a new alternator, I knew the alternator was working fine based on my testing with the volt/ohm meter, took the 2010 Nissan to a Nissan shop…battery NFG. Service manager told me when they replace batteries they alway replace with maintenance free lead acid battery. His claim was the AGM have a different charge profile than lead acid batteries and he wasn’t convinced that all vehicles will charge an AGM properly. Don’t know if it true or not. If your owners manual doesn’t specifically state that AGM are ok then his suggestion was to stay away from them.

I’m guessing your chargers will recognize your AGM battery and charge accordingly but will the Jeep?

I’d still test the alternator output…process of elimination.

 

[Whitenuckler]

I’m not convinced that AGM batteries are the answer for all vehicles.

Had an issue last winter, purchased a AGM which was NFG from the get go. One shop claimed the new battery passed a load test therefore you might need a new alternator, I knew the alternator was working fine based on my testing with the volt/ohm meter, took the 2010 Nissan to a Nissan shop…battery NFG. Service manager told me when they replace batteries they alway replace with maintenance free lead acid battery. His claim was the AGM have a different charge profile than lead acid batteries and he wasn’t convinced that all vehicles will charge an AGM properly. Don’t know if it true or not. If your owners manual doesn’t specifically state that AGM are ok then his suggestion was to stay away from them.

I’m guessing your chargers will recognize your AGM battery and charge accordingly but will the Jeep?

I’d still test the alternator output…process of elimination.

The AGM's are supposed to be better than flooded and the original 2012 was in there until I tried this Amazon supplied battery.
They would have used a cheaper battery, but the battery is inside the truck.
Yes AGM is different, but not much in voltage profile. I believe it has a bigger 100% charge voltage.
The truck has 14.5V on it when I drive, so the alternator must be good.
My cheap 1.75A charger has no selection for AGM.
I just hope the battery is good as I either have to put the old one back in or buy a new one.
The charger being bad is not an issue, and that could be my problem. I have only been doing short drives so if I am leaving the house at 50% after just starting, it may not get a chance to recharge going for a 10 minute drive and low speed.
I will wait till it's charged and do a crank test in -12C.That should prove something.

 

[Murray01]

The AGM's are supposed to be better than flooded and the original 2012 was in there until I tried this Amazon supplied battery.
They would have used a cheaper battery, but the battery is inside the truck.
Yes AGM is different, but not much in voltage profile. I believe it has a bigger 100% charge voltage.
The truck has 14.5V on it when I drive, so the alternator must be good.
My cheap 1.75A charger has no selection for AGM.
I just hope the battery is good as I either have to put the old one back in or buy a new one.
The charger being bad is not an issue, and that could be my problem. I have only been doing short drives so if I am leaving the house at 50% after just starting, it may not get a chance to recharge going for a 10 minute drive and low speed.
I will wait till it's charged and do a crank test in -12C.That should prove something.

Agreed. Battery issues rarely appear in the summer…where’s the fun in changing out a battery in the middle of the summer?

Good luck getting it sorted out

 

[johneh]

A carbon pile battery test uses a variable resistor (the carbon pile) to apply a heavy, controlled load (half the battery's CCA) for 15 seconds, checking if the voltage stays above 9.6V; this simulates starting the engine to assess battery health, ensuring it's fully charged and has clean terminals for accurate results, revealing if a battery can deliver its rated power or is failing.
You also want to see the recovery time if the voltage stays under 11 volts; the battery is on its last legs

 

[Whitenuckler]

A carbon pile battery test uses a variable resistor (the carbon pile) to apply a heavy, controlled load (half the battery's CCA) for 15 seconds, checking if the voltage stays above 9.6V; this simulates starting the engine to assess battery health, ensuring it's fully charged and has clean terminals for accurate results, revealing if a battery can deliver its rated power or is failing.
You also want to see the recovery time if the voltage stays under 11 volts; the battery is on its last legs

Went out an unplugged the charger. It was up to 100%. Did some snow shovelling, and went back after about 20 minutes and did the crank test. Then did the charging test. This was all at -12C. Then I put the battery charger in maintain mode. Before it was in normal charge mode. Maintain is supposed to shut off and restart as required. That curve might give me a good idea of the parasitic draw.

 

[Whitenuckler]

I see what the problem is/was with the small 1.8A charger I am using. The one I had in there before let the voltage go down to 12.27V, and I'm not sure if it would have come on in. I must have left it in maintain mode, as if it were in charge mode, it would not have shut off. I have the "bad" one hooked up to another battery in the garage and will keep an eye on it.

The "new" one I put in yesterday was left on "maintain mode" so I could get a curve of how it works.
The voltage got down to 12.34V (55% Charge) and then switched on.
I am not going to use that mode anymore, as an AGM voltage profile is higher, so it is letting it get too drained if set up for a flooded.
In one hour the voltage dropped from 12.43 to 12.38 so 0.05V per hour. That is with the battery charger still connected and the BM200.
I will need to hook a meter up to the battery neg and measure the milliamp parasitic draw.
I conclusion, I recommend these BM200. I am impressed with the quality of the data, and the crank/charge test. Very good app. Good trend screens.
I am able to hold it near my kitchen window about 30 ft from the truck and update the data.
My battery seems good, the problem was that it was not getting charged properly and I didn't know.

 

[Murray01]

You did mention lots of short trip previously, that will discharge a battery fast.

 

[Whitenuckler]

You did mention lots of short trip previously, that will discharge a battery fast.

Agreed. If it's really cold, and you start your car using a partially discharged battery, you have used up some capacity. Then if you drive a short distance and shut it off, and come back later for another start. It could be a problem. I am really happy I have a handle on this now. At least when I leave the house now I'll be at 100%.