Overriding a "smart" battery management system

[SpitFire6]

Sounds like you have a problem with the ELD or elsewhere or your method of battery voltage readings is wrong.
Battery voltage can not just jump from 12.3 v to 14.2 volts for example in one second on a healthy system?

From the info below:

Alternator Charging Voltage

www.odyclub.com

It's not normal AKA a fault.

 

[wrcsixeight]

A voltage regulator sending the alternator rotor next to no field current,, then fully fielding it with 4 to 5 amps of current, can certainly raise battery voltage that much in a second as the alternator goes from little output to 60+ amps.

A huge healthy well depleted battery would require much more time of more amperage applied for voltage to raise that quickly,

My group 31 Northstar AGM depleted to about 35% state of charge, accepts 134 amps for about 9 minutes before battery terminal voltage rises to 14.7v but this is a thin plate pure lead AGM battery with very low resistance and is still quite new and healthy. The amperage required and the time it requires to be boght to 14.7v at the same depletion level, will just become less and less as it ages. Same with all lead acid batteries, but most all are starting from a lower level of capability initially, as not every vehicle needs 1150CCA or to carry around a 78 Lb battery with such capabilities.

Most car sized starting batteries of median health and depletion levels, can be brought to high voltages, at its terminals, nearly instantly with a large amperage charging source seeking to bring it to high voltages, and most alternators today can easily produce 40+ amps at idle, when fully fielded, and some can easily double this, but only when sent lots of current to the rotor by the voltage regulator, where ever it might be located in the vehicle.

When one has a voltage dial and a huge amperage charging source to achieve that chosen voltage at the battery terminals, and an ammeter, and a voltmeter, it becomes quite obvious how it all works and who does and who does not have any understanding of it, and 99% of people who post online, and think they got it all figured out, do not, but instead keep repeating old wives tales as incontrovertible fact when actual data and reality prove the exact opposite.

I post this as having been one of those completely misunderstanding the topic years ago, and that misunderstanding was not fixed by reading others opinions online, but by collection of data in actual and lots of interest and experimentation and observations of trends and tendencies while watching and tweaking variables which affect the results.

 

[circuitsmith]

Battery voltage can not just jump from 12.3 v to 14.2 volts for example in one second on a healthy system?

It sure can if the battery is in a decent state of charge and the alternator can deliver 50+ amps if need be.

 

[philipp10]

Some of us make an extra effort to take care of our stuff. Strange concept I know.

Optimized to save fuel. Not optimized for infrequent short trips.

Turning on the headlights increases battery voltage.
Couldn't do much night driving if turning on the headlights drained the battery.
Perhaps you should look on youtube for a tutorial on electrical basics.

Well guess I missed the part in my manual where I need to pull my battery every 3 months to charge it....

 

[supton]

Just replaced the 10 year old battery in my truck. Only thing I ever did was to jump start it once after draining to under 9V one winter (some electronic fluke left a light on, overnight). I wonder if my batteries will survive now, pre-pandemic my vehicles generally got several hours of use a month, often an hour at a time, now stuff sits for a week at a time, sometimes two. I may have to drag out some float chargers at some point.

I have to wonder just how much mpg they really are saving... With LED lighting, having buss voltage all over the place isn't the problem it used to be (once you add an LED driver input voltage becomes less of a problem), but the battery life would bug me. Still. A new battery every 5 years seems par for the course. Sooner if in the south, longer if in the north, sure. As long as I can get a Wallyworld replacement for $100 and get 5+ years... just seems minor compared to depreciation. But I sure hope that mpg saving pays for that battery. Just one more thing "for my good" with the implied "but you're supposed to change your vehicle every 5 years anyhow!"

I'm surprised the owners manual doesn't have a proactive battery replacement schedule. Nothing lasts forever.

 

[Jetronic]

Every service we are obliged to test the battery with a Midtronics tester. Only 2 years warranty on original batteries, I guess that's why. Replacements get 3 year...

 

[ondarvr]

Honda covers the battery under the warranty period of 3 years.

Many batteries fail in the first year due to sitting dead on the lot prior being sold. They get charged and driven off the lot, but don't last long.

If a customer complains of a dead battery, Honda will charge the battery, test the charging system, then tell the customer they couldn't find a problem. A week later the battery is dead again. Another visit or two is needed for them install a new battery.

Both of my Hondas had dead batteries on the lot, they put in new batteries before I took them home.

This is one of the most common posts on CRV forums.

I use a smart charger on my Hondas, the older F150 doesn't need one.

 

[Kira]

My 2005 Ranger is said to have a 14.5v-14.9v "Quick Recharge" cycle programmed into it's charging system.

After 5 minutes the rate is said to drop to 13.5v - 13.8v.

The battery which came with the truck was >6.5 years old and settled down below 12v (11.6v comes to mind) overnight so I replaced it.

I'm sure the wisdom of my prudent purchase is canceled out by selecting a Walmart battery.

Group 59 batteries were scarce and Wally's was that month's vintage! Pop used to say, "buy where they run out once in a while because they get fresh".

 

[The Critic]

With my previous 2006 Toyota Matrix I replaced the original battery after 9 years.
It was still going strong, but I didn't feel comfortable going through a 10th winter.
I used to take the battery out and charge every 3 months in my basement overnight at 14.5V.

Is there a need to remove the battery? I just connect my battery charger to the terminals and perform a full charge and balance cycle once-a-week. Spend $80-$100 on a decent battery charger. It's a good tool to have.

 

[gathermewool]

It sure can if the battery is in a decent state of charge and the alternator can deliver 50+ amps if need be.

What is going on here, with all of these people posting nonsense!?

Good on you for setting them straight.

 

[circuitsmith]

Is there a need to remove the battery?

Yes.
I park on a city street. Even when I get a space directly in front of my house I would not run an extension cord across the sidewalk.
That would be an invitation for denizens of the night to investigate.
Once, with my previous car, my doors didn't lock because the hatch as ajar and someone rifled through my glove box and stole my eyeglasses.
Guess they were frustrated that nothing else of value was in there.
Yes, people roam the streets trying car doors.

 

[circuitsmith]

I'm sure the wisdom of my prudent purchase is canceled out by selecting a Walmart battery.

When I buy batteries at WalMart I carry a multimeter and pick the one with the highest standing voltage.

 

[SwampSurvivor]

Yes.
I park on a city street. Even when I get a space directly in front of my house I would not run an extension cord across the sidewalk.
That would be an invitation for denizens of the night to investigate.
Once, with my previous car, my doors didn't lock because the hatch as ajar and someone rifled through my glove box and stole my eyeglasses.
Guess they were frustrated that nothing else of value was in there.
Yes, people roam the streets trying car doors.

When I lived in a city I had that happen a few times. They would go through my vehicles and turn the dome light on or headlights on to completely drain the battery.

 

[SatinSilver]

With my previous 2006 Toyota Matrix I replaced the original battery after 9 years.
It was still going strong, but I didn't feel comfortable going through a 10th winter.
I used to take the battery out and charge every 3 months in my basement overnight at 14.5V.

Do you miss the Matrix at all? I have an 05 here.

 

[circuitsmith]

Do you miss the Matrix at all?

Very much. A hit-and-run totaled it in 2017. I would surely still have it otherwise.
I miss the stickshift too. However, my (ageing) leg would get sore and cause anxiety when I occasionally got stuck in stop-and-go traffic on the interstate for hours.

 

[Flyingdutchman]

I am not sure if it was mentioned before but with my bmw e90 i have to code the car when installing a new battery so that the IBS intelligent batter system know what kind of battery is installed, agm or flooded And how many amps so that it knows how much/long it should charge and the time accesoiries may work or if they are not allowed to switch on.

Also when you do this the system recons that you install a brand new battery with 0 wear so installing a used battery is not wise.

The IBS calculates the age with internal resistance, amount of starts, amount of running hours, load test, amp drops whilr starting etc...

So i dont know if that is also the case with your car. If the computer is told if it is a different kind of battery the charging behavior might change.

 

[circuitsmith]

So i dont know if that is also the case with your car.

Nobody complicates things like BMW and the other German makes.

I have a colleague who likes to buy and tinker with 7-series beemers.
His alternator cooling fan failed; we happen to have lots of 12V fans of various sizes where we work.
Couldn't use one because the fan sends a speed signal to the engine computer.
So he had to pay $$$ for the OEM unit.
I'd never even seen another car with an electric alternator cooling fan.

 

[Flyingdutchman]

Nobody complicates things like BMW and the other German makes.

I have a colleague who likes to buy and tinker with 7-series beemers.
His alternator cooling fan failed; we happen to have lots of 12V fans of various sizes where we work.
Couldn't use one because the fan sends a speed signal to the engine computer.
So he had to pay $$$ for the OEM unit.
I'd never even seen another car with an electric alternator cooling fan.

Yea i agree with you on that, however if it works its nice.
Me personaly i am always interested in these kind of technologys and what goes on in the background.

However with fault finding, especially for people that dont know it it is almost impossible.

 

[4WD]

Yea i agree with you on that, however if it works its nice.
Me personaly i am always interested in these kind of technologys and what goes on in the background.

However with fault finding, especially for people that dont know it it is almost impossible.

Guy I’m working with had so much trouble with his BMW system … that he finally put a Perko switch in and never had a dead battery again … he lives in New Orleans so not a bad idea anyway
(3rd vehicle) …

 

[Flyingdutchman]

Guy I’m working with had so much trouble with his BMW system … that he finally put a Perko switch in and never had a dead battery again … he lives in New Orleans so not a bad idea anyway
(3rd vehicle) …

Okay did he had a dead battery after a short while?
In the beginning of covid my bmw wasnt used for over 3 months due to having a work van.

When i started it after 3 months it started just as easy like it had ran that morning.

In the IBS it monitors the residiual current.
Also after about 30 seconds it switches off everything except for the alarm and reciever for the car key.
The IBS wakes up every x amount of time to see what the state is and then goes in sleep mode again.