HYBRID 12V Battery Mystery SOLVED

[HeyBales]

@HeyBales, Sorry for resurrecting this post from page 13 of this thread, but I have a theory that I would like to have you consider!
I don't have the tools, time or patience to pursue it, but you always seem game!
My theory pertains to this statement of your's:
"Sorry if this is coming off harsh - but I keep seeing this disconnect between 2 different problems.
And I'm always posting about someone checking on the ACCM update when they report a drain condition.
But this thread is the first time something has been found to force higher charging to keep a battery from getting undercharged and slowly go bad.
It's not doing that because there was a parasitic drain, just the normal micro-drain."

I agree! Two completely separate and battery damaging parasitic drains!

My theory (which I can in no way prove or defend):
These two parasitic drain happen independently and at different times.
One of these, the conventional parasitic drain comes upon vehicle shutdown and drains the battery! Ecoboost and/or hybrid - makes no difference.
The other parasitic drain, the one that happens as soon as the (mostly? hybrids) vehicle is turned on - causing the DC to DC converter to kick into action!
This parasitic draw is huge! Enough to drop my 2025XL's 70mph gas mileage from the 36 -37mpg I am currently seeing, down to the 30mpg I was getting before the trailer module update!
The trailer update has fixed this huge parasitic draw! Just like the ingenious "headlights on, wipers on, parking lights on, rear seat 120V outlet usage, and hitch brake light on" hack has been shown to circumvented this same parasitic draw!

The TMU came too soon for me to test whether the hitch light etc. would have increased my highway mpg, in addition to normalizing my 12V battery charging!
I hope someone who hasn't had the TMU yet can test that.

How can a parasitic huge drain reduce gas mileage?
Easy, the motor generator has to work at essentially 100% output (for it's given engine speed?) to satisfy the parasitic electrical drain.

Why doesn't the battery get charged?
Likely, the vehicle's electrical systems' "need" has first dibs on the electrical power supplied by the DC to DC converter, so the battery gets starved...Until higher speeds and longer drives allow the motor generator to finally supply enough electrical supply to satisfy both vehicle needs and battery charging!

That's it!
I'll entertain questions, but it is unlikely that I will be to answer any of them! What we need (I think) is a hybrid vehicle electrical design engineer.

Some interesting ideas.
Usually parasitic is not the term used on known expected power draws, which are normally small too. Parasitic for undesired sucking energy, not small. Confusingly a parasite is small also.
Think key fob usage for decades - requires a receiver on 24/7. Alarm system, remote monitoring, ect. None of that is new and been going on for ages and at some level desired.

That micro-drain is only damaging if you don't drive enough to replenish it. (25-50 mA on 45Ah battery - 900 hrs on short high draw side - 37 days)
But in very old cars where off is off, no draw - very infrequently driven did cause battery drain, and if the drives were too short to charge it back up - battery died sooner than it would have otherwise.

So no different than that with truck - that should frankly be expected. And likely the reason for the misguided "drive more" suggestion when it likely didn't apply often.

Parasitic drains aren't always small either, just not expected. Think of the ABS or AC or TCU module staying "up" drawing 1-2 Amps for hours until battery is so low some system shut everything down, or in old vehicles a simple light left on that didn't turn off.

This purposely designed undercharging to a max SOC% is a charging strategy, not a parasitic drain. It is desired by the engineers for whatever reason (I think safety of battery in cabin).

Just wanted to make a clear distinction between non-desired vs designed. (parasitic 0.5-3A and micro-drain 25-50 mA)

I really wonder what that TRM update did, to improve highway mileage. But it's not what you are thinking.

The whole 12V system running, even with fan speeds and headlights is really barely an impact to the HV system - it's not a drain that requires anywhere near 100% Generator Motor power.
I've got a video that happens to show a 30A charge to the 12VB after startup, DCDC 12V system at 36A for everything including that - and since no ICE running the HVB is supplying all that - only 2.5 A from DCDC. That's nothing, no AC running, so that's all to the 12V system, converted.
Anyone with a scanner has probably seen the barely impact to the HV system from the 12V system being fed from the DCDC and HV system.

There is no change to 12V charging Amps based on speed or ICE running. Not a tick.
Purely 12VB SOC%. (perhaps to lesser extent the logged Amp-hours of charge/discharge totals. Or maybe that is only used to calculate SOC% once a load/charge starts - can't get a decent SOC% figure anytime near a charge or discharge based on voltage, it's inaccurate)
Also battery temps from what I've seen.
That's what determines normally how much charge the 12VB is getting.
That's why I've always described the hybrid as having a built in battery charger - totally controlled. Just not very well.

And the strategy says if at 85% SLA or 92% AGM reached - allow the 12VB to juice the 12V system until the SOC drops, instead of the HV system.

The methods found tell the system to ignore the presets - go for 100%, and at higher Amp rate than the float charge normally done.
Is it because in all those methods you could drop to On-only mode and keep those systems going, causing too much 12V draw in a short time, which would drain the HVB kinda fast, with no ability to recharge with ICE turning on?
In On-mode, when the HVB reaches 30% - the 12VB powers all that 12V system - now it will drain fast, before the truck turns off for you.
A setting allows headlamps to remain on for 2 min even after truck off and door opened.
Fan will remain running in On-mode. Spd 6 is big 3A higher draw than spd 5.
Could Trailer hitch provide power for a big draw trailer lighting system in On-mode?

As to why did your mileage improve at highway speeds after a module update?

The 12VB being used to juice the 12V system when SOC reaches 92%, instead of the HV system - might be draining the 12VB (by design so not parasitic), but it saves the HV system and HVB from doing it. That's a potential gas savings with ICE running less to charge the HVB.
The 12VB continuing to be charged at higher rate over 92% by the HV system, would be the worse mileage as the HVB might need more charging with ICE running more.
This is opposite of your comment.

It would be interesting after the TRM update - since the 92% for AGM is still the upper limit, but rather for your battery with a potential problem, is a lower limit still about 88%? Maybe they lowered that to 80%, so your BMS is willing to charge higher now than before, in prep for supporting a trailer plugged in with unknown potentially higher draw?
That would help your battery.
But @rslilly76 had the update too, and already confirmed no change to upper value.
https://www.mavericktruckclub.com/forum/threads/hybrid-12v-battery-mystery-solved.81553/post-1371531

Here's a simple thing they could do with that update for mileage - someone would need to look at some values in a scanner before & after.
Did having something plugged in to hitch do more than just cause the 12VB to be charging faster/higher?
(again - that ain't much load on the HV system to make a huge change to mileage because the HVB is being drained)
Did it use to cause a Tow/Haul drive mode type effect - where the Traction motor was used more for supplying power to supplement the engine power? In Tow mode that causes ICE to be on to supply that extra charging to keep the HVB near 70%, and use extra power with the ICE.
But if ICE isn't running constantly in Normal mode, the HVB is just being drained faster, requiring more ICE on time anyway.
Could it have been doing that with something plugged into the hitch - when it really wasn't needed?
Now you got an update - and that effect is only done in Tow/Haul mode?

That is total theory - but that should affect mileage. Should be noticeable though - like not hearing the ICE now on slight declines where before it would be running.

@rslilly76 - are you on the highway enough at 70 mph to notice a difference in mileage pre/post TRM update?

I'm assuming this is instantenous mileage reading.

Sponsored

 

[Finnster]

Some interesting ideas.
Usually parasitic is not the term used on known expected power draws, which are normally small too. Parasitic for undesired sucking energy, not small. Confusingly a parasite is small also.
Think key fob usage for decades - requires a receiver on 24/7. Alarm system, remote monitoring, ect. None of that is new and been going on for ages and at some level desired.

That micro-drain is only damaging if you don't drive enough to replenish it. (25-50 mA on 45Ah battery - 900 hrs on short high draw side - 37 days)
But in very old cars where off is off, no draw - very infrequently driven did cause battery drain, and if the drives were too short to charge it back up - battery died sooner than it would have otherwise.

So no different than that with truck - that should frankly be expected. And likely the reason for the misguided "drive more" suggestion when it likely didn't apply often.

Parasitic drains aren't always small either, just not expected. Think of the ABS or AC or TCU module staying "up" drawing 1-2 Amps for hours until battery is so low some system shut everything down, or in old vehicles a simple light left on that didn't turn off.

This purposely designed undercharging to a max SOC% is a charging strategy, not a parasitic drain. It is desired by the engineers for whatever reason (I think safety of battery in cabin).

Just wanted to make a clear distinction between non-desired vs designed. (parasitic 0.5-3A and micro-drain 25-50 mA)

I really wonder what that TRM update did, to improve highway mileage. But it's not what you are thinking.

The whole 12V system running, even with fan speeds and headlights is really barely an impact to the HV system - it's not a drain that requires anywhere near 100% Generator Motor power.
I've got a video that happens to show a 30A charge to the 12VB after startup, DCDC 12V system at 36A for everything including that - and since no ICE running the HVB is supplying all that - only 2.5 A from DCDC. That's nothing, no AC running, so that's all to the 12V system, converted.
Anyone with a scanner has probably seen the barely impact to the HV system from the 12V system being fed from the DCDC and HV system.

There is no change to 12V charging Amps based on speed or ICE running. Not a tick.
Purely 12VB SOC%. (perhaps to lesser extent the logged Amp-hours of charge/discharge totals. Or maybe that is only used to calculate SOC% once a load/charge starts - can't get a decent SOC% figure anytime near a charge or discharge based on voltage, it's inaccurate)
Also battery temps from what I've seen.
That's what determines normally how much charge the 12VB is getting.
That's why I've always described the hybrid as having a built in battery charger - totally controlled. Just not very well.

And the strategy says if at 85% SLA or 92% AGM reached - allow the 12VB to juice the 12V system until the SOC drops, instead of the HV system.

The methods found tell the system to ignore the presets - go for 100%, and at higher Amp rate than the float charge normally done.
Is it because in all those methods you could drop to On-only mode and keep those systems going, causing too much 12V draw in a short time, which would drain the HVB kinda fast, with no ability to recharge with ICE turning on?
In On-mode, when the HVB reaches 30% - the 12VB powers all that 12V system - now it will drain fast, before the truck turns off for you.
A setting allows headlamps to remain on for 2 min even after truck off and door opened.
Fan will remain running in On-mode. Spd 6 is big 3A higher draw than spd 5.
Could Trailer hitch provide power for a big draw trailer lighting system in On-mode?

As to why did your mileage improve at highway speeds after a module update?

The 12VB being used to juice the 12V system when SOC reaches 92%, instead of the HV system - might be draining the 12VB (by design so not parasitic), but it saves the HV system and HVB from doing it. That's a potential gas savings with ICE running less to charge the HVB.
The 12VB continuing to be charged at higher rate over 92% by the HV system, would be the worse mileage as the HVB might need more charging with ICE running more.
This is opposite of your comment.

It would be interesting after the TRM update - since the 92% for AGM is still the upper limit, but rather for your battery with a potential problem, is a lower limit still about 88%? Maybe they lowered that to 80%, so your BMS is willing to charge higher now than before, in prep for supporting a trailer plugged in with unknown potentially higher draw?
That would help your battery.
But @rslilly76 had the update too, and already confirmed no change to upper value.
https://www.mavericktruckclub.com/forum/threads/hybrid-12v-battery-mystery-solved.81553/post-1371531

Here's a simple thing they could do with that update for mileage - someone would need to look at some values in a scanner before & after.
Did having something plugged in to hitch do more than just cause the 12VB to be charging faster/higher?
(again - that ain't much load on the HV system to make a huge change to mileage because the HVB is being drained)
Did it use to cause a Tow/Haul drive mode type effect - where the Traction motor was used more for supplying power to supplement the engine power? In Tow mode that causes ICE to be on to supply that extra charging to keep the HVB near 70%, and use extra power with the ICE.
But if ICE isn't running constantly in Normal mode, the HVB is just being drained faster, requiring more ICE on time anyway.
Could it have been doing that with something plugged into the hitch - when it really wasn't needed?
Now you got an update - and that effect is only done in Tow/Haul mode?

That is total theory - but that should affect mileage. Should be noticeable though - like not hearing the ICE now on slight declines where before it would be running.

@rslilly76 - are you on the highway enough at 70 mph to notice a difference in mileage pre/post TRM update?

I'm assuming this is instantenous mileage reading.

My post is just a theory to be be considered since I don't have the ability to investigate it myself.

As far as the parasitic drag I believe I am seeing, it is a huge parasitic drag, not the small milliamp drags associated with conventional electronic components.

The tow/haul mode idea is interesting, but I can't really evaluate that effectively either.
Along with the improvement I have seen in battery/charging since the trailer module update, I have also noticed that the Electric mode is more eager to spontaneously take over than it was pre-update. Not a huge difference, but certainly noticable (FWIW).

As to the (instantaneous or not?) mileage numbers that I have reported on my, pre and post update, gas mileage reports: those numbers are cumulative results as shown on my average economy display on the on the drivers display.
The comparison isn't perfect as I had to base the "pre-update" highway number on what I have seen over the last 11 months pre-update.
I wish I would have known to do a "pre" mileage test, but I never associated a trailer update with a possible jump in mpg's.
So it is true, this is only a theory with absolutely no verifiable data! I will continue to watch my maverick hybrid's battery situation to see where it goes from here!
My hope is that some curious hybrid owners will try to confirm my suspicion that the trailer module update has normalized or maybe fixed the 12V battery charging problems we are seeing, and that their highway mpg's have increased since the update.
I am also hopeful that the TM update will help MY22-24 when it becomes available.
Good luck to all!

 

[Red Eyes - Wide Shut]

PLEASE get the ABS and ACCM updates done and share with us if it worked short and long term. I don't know if anyone has had the most recent updates performed to see if they actually work. Right now we're debating what we think will or won't work

Talked to service writer and he said he knew of no updates that you mentioned that would help. How do I know if I have those updates. Are they over the air, recalls or SSM's

He said drive it more and turn off auto updates. From his comments nothing is really being done by corporate and left to the dealerships.

 

[rslilly76]

Some interesting ideas.
Usually parasitic is not the term used on known expected power draws, which are normally small too. Parasitic for undesired sucking energy, not small. Confusingly a parasite is small also.
Think key fob usage for decades - requires a receiver on 24/7. Alarm system, remote monitoring, ect. None of that is new and been going on for ages and at some level desired.

That micro-drain is only damaging if you don't drive enough to replenish it. (25-50 mA on 45Ah battery - 900 hrs on short high draw side - 37 days)
But in very old cars where off is off, no draw - very infrequently driven did cause battery drain, and if the drives were too short to charge it back up - battery died sooner than it would have otherwise.

So no different than that with truck - that should frankly be expected. And likely the reason for the misguided "drive more" suggestion when it likely didn't apply often.

Parasitic drains aren't always small either, just not expected. Think of the ABS or AC or TCU module staying "up" drawing 1-2 Amps for hours until battery is so low some system shut everything down, or in old vehicles a simple light left on that didn't turn off.

This purposely designed undercharging to a max SOC% is a charging strategy, not a parasitic drain. It is desired by the engineers for whatever reason (I think safety of battery in cabin).

Just wanted to make a clear distinction between non-desired vs designed. (parasitic 0.5-3A and micro-drain 25-50 mA)

I really wonder what that TRM update did, to improve highway mileage. But it's not what you are thinking.

The whole 12V system running, even with fan speeds and headlights is really barely an impact to the HV system - it's not a drain that requires anywhere near 100% Generator Motor power.
I've got a video that happens to show a 30A charge to the 12VB after startup, DCDC 12V system at 36A for everything including that - and since no ICE running the HVB is supplying all that - only 2.5 A from DCDC. That's nothing, no AC running, so that's all to the 12V system, converted.
Anyone with a scanner has probably seen the barely impact to the HV system from the 12V system being fed from the DCDC and HV system.

There is no change to 12V charging Amps based on speed or ICE running. Not a tick.
Purely 12VB SOC%. (perhaps to lesser extent the logged Amp-hours of charge/discharge totals. Or maybe that is only used to calculate SOC% once a load/charge starts - can't get a decent SOC% figure anytime near a charge or discharge based on voltage, it's inaccurate)
Also battery temps from what I've seen.
That's what determines normally how much charge the 12VB is getting.
That's why I've always described the hybrid as having a built in battery charger - totally controlled. Just not very well.

And the strategy says if at 85% SLA or 92% AGM reached - allow the 12VB to juice the 12V system until the SOC drops, instead of the HV system.

The methods found tell the system to ignore the presets - go for 100%, and at higher Amp rate than the float charge normally done.
Is it because in all those methods you could drop to On-only mode and keep those systems going, causing too much 12V draw in a short time, which would drain the HVB kinda fast, with no ability to recharge with ICE turning on?
In On-mode, when the HVB reaches 30% - the 12VB powers all that 12V system - now it will drain fast, before the truck turns off for you.
A setting allows headlamps to remain on for 2 min even after truck off and door opened.
Fan will remain running in On-mode. Spd 6 is big 3A higher draw than spd 5.
Could Trailer hitch provide power for a big draw trailer lighting system in On-mode?

As to why did your mileage improve at highway speeds after a module update?

The 12VB being used to juice the 12V system when SOC reaches 92%, instead of the HV system - might be draining the 12VB (by design so not parasitic), but it saves the HV system and HVB from doing it. That's a potential gas savings with ICE running less to charge the HVB.
The 12VB continuing to be charged at higher rate over 92% by the HV system, would be the worse mileage as the HVB might need more charging with ICE running more.
This is opposite of your comment.

It would be interesting after the TRM update - since the 92% for AGM is still the upper limit, but rather for your battery with a potential problem, is a lower limit still about 88%? Maybe they lowered that to 80%, so your BMS is willing to charge higher now than before, in prep for supporting a trailer plugged in with unknown potentially higher draw?
That would help your battery.
But @rslilly76 had the update too, and already confirmed no change to upper value.
https://www.mavericktruckclub.com/forum/threads/hybrid-12v-battery-mystery-solved.81553/post-1371531

Here's a simple thing they could do with that update for mileage - someone would need to look at some values in a scanner before & after.
Did having something plugged in to hitch do more than just cause the 12VB to be charging faster/higher?
(again - that ain't much load on the HV system to make a huge change to mileage because the HVB is being drained)
Did it use to cause a Tow/Haul drive mode type effect - where the Traction motor was used more for supplying power to supplement the engine power? In Tow mode that causes ICE to be on to supply that extra charging to keep the HVB near 70%, and use extra power with the ICE.
But if ICE isn't running constantly in Normal mode, the HVB is just being drained faster, requiring more ICE on time anyway.
Could it have been doing that with something plugged into the hitch - when it really wasn't needed?
Now you got an update - and that effect is only done in Tow/Haul mode?

That is total theory - but that should affect mileage. Should be noticeable though - like not hearing the ICE now on slight declines where before it would be running.

@rslilly76 - are you on the highway enough at 70 mph to notice a difference in mileage pre/post TRM update?

I'm assuming this is instantenous mileage reading.

I've seen no change in my mpg due to the trailer module update
I've seen no change in charging scheme at all

I've had the trailer light plugged and unplugged testing it both ways. I didn't see any differences.

 

[Finnster]

I've seen no change in my mpg due to the trailer module update
I've seen no change in charging scheme at all

I've had the trailer light plugged and unplugged testing it both ways. I didn't see any differences.

Well that's a buzzkill!
I thought you had noticed a drop in your running voltage supplied to the 12V battery (15.1 - 14.8?) upon plugging in the hitch brake light?
Don't tell me I got that wrong too!
I honestly thought I had discovered the "Oak Island Mystery"! No cameo for me I guess, just fool's gold, Lol.

OK, Theory 6b:
Noticing the the drop in 12V battery voltage supplied that happened concurrently with receiving my 2025 hybrid's Trailer Module update and recognizing that my truck was operating more efficiently , I immediately headed out to the highway and took the longest uninterrupted highway trip (32 miles @70mph) that my truck has ever had, and I recorded my best ever mpg result!
The wild card which I had thought was only marginally important was that I had just headed out on this test run on Wisconsin's first scorchingly hot afternoon of the year (90F. degrees)!
With all other options having been ruled out by @rslilly76, I guess all that leaves is the increased efficiency of my 11 month old 12V battery caused by the 40F. degree jump in ambient temperature, and the longer running time of this single trip! (battery charge time?)
Well, that and some gained efficiency from reduced aerodynamic drag and mechanical drag due to the increased temperature.
At least I enjoyed this lark, but I'll fully understand if not everyone did! Time for me to lurk for a bit!
Thanks for listening!

 

[Hootbro]

Thanks for drilling down on this and am glad I found this thread.

I bought my 2026 Maverick XL AWD Hybrid (2-26 build date) a couple of weeks ago and recently put it on a NOCO Genius 5 trickle charger the last couple of days and was wondering why it would not keep a SOC past 86% over time? I changed lead positions of the charger to a different ground and it briefly popped up to 100% SOC and now has settled down in the mid 80's% SOC again.

Plan is tonight plug in a Curt Trailer Plug tester that simulates a trailer and see if that tricks the charge profile to go to 100% SOC and maintains? If that does the trick, will leave that on as a work around to when or if the software gets changed on this charging system.

 

[SafetyGuy]

Thanks for drilling down on this and am glad I found this thread.

I bought my 2026 Maverick XL AWD Hybrid (2-26 build date) a couple of weeks ago and recently put it on a NOCO Genius 5 trickle charger the last couple of days and was wondering why it would not keep a SOC past 86% over time? I changed lead positions of the charger to a different ground and it briefly popped up to 100% SOC and now has settled down in the mid 80's% SOC again.

Plan is tonight plug in a Curt Trailer Plug tester that simulates a trailer and see if that tricks the charge profile to go to 100% SOC and maintains? If that does the trick, will leave that on as a work around to when or if the software gets changed on this charging system.

Good day, @Hootbro

Yes, there is a lot of good info here in the discussion.

As you have a pretty new truck (congratulations, I hope you love yours as much as we love ours!), I think it is a good idea to make sure the truck charges your battery to its maximum, as it probably hasn't been done properly yet).

I suggest to charge your 12 volt battery so it is completely charged...then disconnect everything and lockup the truck for 9 hours.

This may take a few tries to get it to do its battery relearn (as per your manual) and save the updated info, but also will help keep your battery charged appropriately, with the other things you have learned here.

Just a thought,

Andy

 

[Finnster]

@Hootbro,
Did you get a chance to try any/all (except hitch brake light of course) of the inspired @Mavster Mechanic hacks before the trailer module update? Observations?
I received the update before I could do any meaningful testing.
Thanks, and welcome to the group!

 

[HeyBales]

Thanks for drilling down on this and am glad I found this thread.

I bought my 2026 Maverick XL AWD Hybrid (2-26 build date) a couple of weeks ago and recently put it on a NOCO Genius 5 trickle charger the last couple of days and was wondering why it would not keep a SOC past 86% over time? I changed lead positions of the charger to a different ground and it briefly popped up to 100% SOC and now has settled down in the mid 80's% SOC again.

Plan is tonight plug in a Curt Trailer Plug tester that simulates a trailer and see if that tricks the charge profile to go to 100% SOC and maintains? If that does the trick, will leave that on as a work around to when or if the software gets changed on this charging system.

So that SOC% is not the Ford's system reading, correct, but an external charger/volt reader where you tell it the battery info?
If no battery info was supplied - it's just using standard table for Voltage = SOC%.

Just be aware that most the posts in this thread are talking about Ford's own calculated SOC%, read straight from their system via scanner.
So your reading won't necessarily match.
In fact - if you aren't providing battery details, and it's not reading amps along with Voltage - that battery monitor can't really give a SOC% while it's being charged or discharged - just not accurate or possible.
Pre running voltage is great though - gives an indication of what direction the battery is going.

If you are talking about plugging in that hitch tester, and then setting up the Noco - wrong idea on the methods given in this thread.

BMS system has no control over an external charger, and truck better not be paying attention to what's in the hitch plug when it's off - otherwise you got a problem.

Those methods given are when the truck is running.
It's for getting the truck's own BMS to charge higher than the 92% SOC.
Your battery monitor seeing 14.x volts while running probably is why it shows 100% SOC.

So where your voltage monitor could come in to play - is when it shows 12.8 V while you are driving at some point.
And you do NOT have headlights on, fan on 6, hitch light plugged in.
That means you reached Ford 92% SOC, and the BMS is willing to stop charging.
Now put one of those on - and you should see Volts go back to 14.x.

Now that you have charged the battery - let that 9 hr Relearn happen Safetyguy mentions.
And you will likely see that 12.8V while driving.

And don't worry about the SOC% in that battery monitor - it won't match probably.
Just morning resting volts.

 

[Hootbro]

@Hootbro,
Did you get a chance to try any/all (except hitch brake light of course) of the inspired @Mavster Mechanic hacks before the trailer module update? Observations?
I received the update before I could do any meaningful testing.
Thanks, and welcome to the group!

No, no yet. Just found this thread this morning while at work. Probably will play with it a bit later tonight when off work.

What lead me here was looking at my battery monitor graphs for the last couple of weeks and was surprised of how little the vehicle charges to 100% SOC. Left work one day on 5/21 and surprise to see the battery SOC drop to 35% just sitting at work for 8 hours. There was no indication it was in any battery saver mode and started up with no issue.

Until this thread, I was perplexed on why it would not charge to or near 100% SOC.

 

[Hootbro]

So that SOC% is not the Ford's system reading, correct, but an external charger/volt reader where you tell it the battery info?
If no battery info was supplied - it's just using standard table for Voltage = SOC%.

I use a ANCEL BM200 batter monitor device that hooks directly to the 12VDC battery. It is setup with the battery type and voltage parameters.

The graphs in my first post is from the last 2.5 days with it sitting just on the NOCO maintainer. Remaining graphs are from days prior when I was driving the vehicle.

 

[HeyBales]

No, no yet. Just found this thread this morning while at work. Probably will play with it a bit later tonight when off work.

What lead me here was looking at my battery monitor graphs for the last couple of weeks and was surprised of how little the vehicle charges to 100% SOC. Left work one day on 5/21 and surprise to see the battery SOC drop to 35% just sitting at work for 8 hours. There was no indication it was in any battery saver mode and started up with no issue.

Until this thread, I was perplexed on why it would not charge to or near 100% SOC.

Regarding your images - be curious to see the Voltage side of it.
That will be better info than SOC due to what I said in last post.
ETA: Knew that was likely the Ancel, many have it. SOC% not as useful as Volts.

Regarding those 2 big dips.
Evening or middle of night?
Early morning or normal morning for you?
Recall doing something in truck with doors open if not middle of the night?

You have OTA updates enabled?
Do you have a set time, or default anytime?
See any updates on those days of the dip?

How is your ATT signal in your area?

 

[Hootbro]

Regarding your images - be curious to see the Voltage side of it.
That will be better info than SOC due to what I said in last post.
ETA: Knew that was likely the Ancel, many have it. SOC% not as useful as Volts.

Regarding those 2 big dips.
Evening or middle of night?
Early morning or normal morning for you?
Recall doing something in truck with doors open if not middle of the night?

Dip was Saturday night into Sunday morning.

You have OTA updates enabled?
Do you have a set time, or default anytime?
See any updates on those days of the dip?

OTA enabled and set for 1 am. Did not check for updates but am familiar with the process as I also own a Bronco Sport.

How is your ATT signal in your area?

Cell signal can be spotty but 60% of the time, works every time. Have also setup to use the house wifi which is a stronger signal

 

[Darryl]

Talked to service writer and he said he knew of no updates that you mentioned that would help. How do I know if I have those updates. Are they over the air, recalls or SSM's

He said drive it more and turn off auto updates. From his comments nothing is really being done by corporate and left to the dealerships.

The service advisor/techs are LAZY. All they have to do is pay attention. If it's a 2025 the TSB is 26-2170. If it's a 2022-2024 it's an SSM . That number is SSM 54785. All they had to do was either
A. Pay attention to the daily bulletins They were issued on April 16th and April 28.
B. Enter the VIN , enter the symptom under battery or no/slow start . Then this bulletin number and some older bulletins would have shown up . Go back ASAP (sometimes the same number changes) and give them the number I gave you based on your model year.

 

[Darryl]

The service advisor/techs are LAZY. All they have to do is pay attention. If it's a 2025 the TSB is 26-2170. If it's a 2022-2024 it's an SSM . That number is SSM 54785. All they had to do was either
A. Pay attention to the daily bulletins They were issued on April 16th and April 28.
B. Enter the VIN , enter the symptom under battery or no/slow start . Then this bulletin number and some older bulletins would have shown up . Go back ASAP (sometimes the same number changes) and give them the number I gave you based on your model year.

Better yet, show this to them . Please don't let them know where you got it.

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