Ford Battery Monitor Reset or Not To Reset

[Fordiesel69]

So I have read 2 different theories. Ford intended the battery monitor algorithm to adapt the charge rate and profile to match the battery as it begins to age, therfore greatly extending the life of the battery and charging system. Then when you replace the battery you will need to go into the PCM and clear the battery monitor parameter and it will then start off fresh at its full charge rate.

The second theory is that this charge algorithm / adaptation actually decreases the life of the battery greatly and that the owners should be resetting this parameter yearly as to not have the charge level decrease, therfore it will act more like a traditional charging system?

Which way is best?

 

[ragtoplvr]

Statistics with a sample size of one do not work. It would be unusual rare for someone other than Ford to have a big enough sample.

An OEM can make a mistake.

I would think an Uber driver would benefit from a different charge algorithm than an elderly couple that drives 1 or 2 days a week.

Batteries from different mfg. may need different charge algorithm. Ove the life of the vehicle battery tech will change and the algorithm would need to change.

I expect that algorithm is NOT designed for max life, but designed to not strand people.

I always recommend replacing battery when reliability is a premium like my parents van, after 3 or 4 years.

anything else is a wild guess unless if comes from the OEM.

 

[Hall]

Theories ? No, wild *** guesses.... Another way to put that is "no one outside of Ford really knows" so why the speculation ?

The part about resetting the BCM when you replace the battery is absolutely valid but I suspect that's only done if you have a Ford dealer do the replacement. Maybe some shops do it, but if Walmart, Autozone, or Joe Smith replace the battery, is it getting reset ? Doubtful. When I replaced the battery in our Ford, I put in a larger one and in addition to resetting the BCM, I told it what size the new battery was so it charges it "more" than it was originally programmed for.

 

[Kawiguy454]

Just Let controller do what it does. The physics of battery types are well known these days to engineers so IMO you'll do best letting it happen.

I believe the main thing the algos continuously do with whatever battery is attached Is measure very small changes in voltage and current draw to estimate remaining capacity/lifetime left. Then precisely control how much charge to apply without destructive overcharging. The slant is toward fuel economy so slight undercharge of battery and not charging under acceleration are paramount. Putting in a new battery the controller should sense and adapt to quickly.

A couple times a year I attach my CTEK and do a full cycle on my vehicles.

 

[Hall]

I thought another function of the battery management system is to "turn off" the alternator when it's not needed, reducing drag on the engine and in turn, better fuel economy. It can't do that without a clutch on the alternator pulley though, can it ?

 

[JustinH]

There is really no reason not to do it.

You can do it with ForScan and a 7 dollar OBD2 dongle with switch on a windows laptop.

I did it when I replaced my battery, because I needed to pull the wipers to get the battery out, and that also needs a relearn procedure from the scantool.

Here is a link I found on what it does.

https://moundalexis.com/v2/2020/08/...lectrical Energy Management system functions.

 

[eljefino]

I thought another function of the battery management system is to "turn off" the alternator when it's not needed, reducing drag on the engine and in turn, better fuel economy. It can't do that without a clutch on the alternator pulley though, can it ?

It could if it wanted to by controlling the field current. Grab a "loose" alternator and spin its pulley, it'll spin free because there aren't electrical demands being placed on it.

 

[zzyzzx]

I used it as an excuse to get an ELM32 adapter and learn how to run ForScan on a Linux laptop.