Powerboost 12v battery charging tip

[marekjk]

Found an interesting twist to this issue of setting the blower to 5 or higher to get the 12 volt battery up to 100% SOC.

If you are sitting in the driver's seat and set the blower to 5 or higher, the voltage will rise to a temperature compensated range of 13.7 volts to 14.2 volts and over time the 12 volt battery will reach 100% SOC.

Now if you open the door and step out of the truck with the engine running and shut the door simultaneously with the "beep beep" of the horn the 12 volt battery voltage will fall to 12.7 volts. Get into the seat and shut the door and the volts will jump back to the 14 volt range.

You can't make this stuff up it is so stupid. What are they thinking?

Wow, good catch. I am with you, what are they thinking?

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[rhymeandreasons]

tricking the EPA Emissions testers. LOL

Wow, good catch. I am with you, what are they thinking?

 

[RyanStroeder]

well it won't deplete it, it will just go down to the 70-80% SOC range. If you have a trailer connected you really want that higher voltage if you're charging any type of batt on the trailer. Fortunately the truck is more than happy to lock with a keyfob in it. The MME doesn't like to lock if it's on or a PAAK phone is in it. You can leave the key in it and use the keypad, another fob, or fordpass to unlock it. The bottom 2 buttons on the keypad pressed together will lock any ford -- that logic has been present over 20 years now.

Thanks so much to you and @Snakebitten! Lots of info here!

Where did the community end up regarding the continual "12V Battery State of Charge Low" problem? Do we leave the blower set to 5 or above? Do we replace with another battery type as listed in other threads?

Open to suggestion here, but so sick and tired of the issues...

 

[Capt JT]

Thanks so much to you and @Snakebitten! Lots of info here!

Where did the community end up regarding the continual "12V Battery State of Charge Low" problem? Do we leave the blower set to 5 or above? Do we replace with another battery type as listed in other threads?

Open to suggestion here, but so sick and tired of the issues...

My local Ford dealer performed the TSB on my truck for this which was a software update and haven't had an issue since. Had a few issues with low battery before but none after. Just FYI.

 

[RyanStroeder]

My local Ford dealer performed the TSB on my truck for this which was a software update and haven't had an issue since. Had a few issues with low battery before but none after. Just FYI.

any chance you know the TSB in question?

 

[Capt JT]

any chance you know the TSB in question?

On my service receipt it says TSB-23-2317 which sounds right. Specifically addressed this issue with low state of charge and no starts. Truck has performed flawless since.

 

[HammaMan]

Thanks so much to you and @Snakebitten! Lots of info here!

Where did the community end up regarding the continual "12V Battery State of Charge Low" problem? Do we leave the blower set to 5 or above? Do we replace with another battery type as listed in other threads?

Open to suggestion here, but so sick and tired of the issues...

I'd see if you have mobile service and can get the BCM updated if it's not already been done. It's more aggressive at charging, but the factory batteries are still pretty meh.

 

[RyanStroeder]

I'd see if you have mobile service and can get the BCM updated if it's not already been done. It's more aggressive at charging, but the factory batteries are still pretty meh.

Thanks, everyone - including @Capt JT

I did a little googling and it looks like an appropriate TSB for my "12V state of charge low" could be TSB 24-2295. Thanks to @GrandpaD for posting it!

I have the truck booked in for mid november to address it. I'll keep everyone posted. Cheers

https://www.f150gen14.com/forum/thr...of-charge-charging-system-service-soon.28947/

 

[powerboatr]

The 12v went to 6.6 in mom's hybrid maverick
I used the noco jump box to get it up enough the hvb engaged and truck ran
Not sure why or how it suddenly worked...then hr later 6.6
It's charge system isvery much like the pb..no alternator for 12v..it all gets charged via hvb through its devices
Thank s to people here I was able to jump start her maverick.
Used the stuff I learned here about the hybrid
Architecture

 

[F150truckr2023]

Folks, thank you so much for your research on this topic. After reading this forum, my dealer finally applied the brand new TSB 25-2142 dated April 30th 2025.

my 12v battery was dying after some minimal AC usage. Hopefully this update will change the BMS to monitor and charge the batteries better. I had to jump start the truck numerous times.

hope this TSB will help others looking for help.

 

[Demps]

Folks, thank you so much for your research on this topic. After reading this forum, my dealer finally applied the brand new TSB 25-2142 dated April 30th 2025.

my 12v battery was dying after some minimal AC usage. Hopefully this update will change the BMS to monitor and charge the batteries better. I had to jump start the truck numerous times.

hope this TSB will help others looking for help.

Updated my 2021 powerboost with FDRS mid June. Modules noted in TSB were updated. Was getting notifications about low battery while sitting in the body shop. No low battery notifications when regularly driven.
Should these updates effectively keep the battery charged enough to eliminate low battery notification if the truck isn’t driven for an extended period of time?
Still necessary to keep A/C fan speed at 5 or above?
Thanks

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