Rookie mistake on 12v battery change

[mattbuilt1]

Also - BMS reset only should be done on new battery, not charged. It's reseting some figures that it should be tracking about battery age and health.
Just let it sit overnight after an evening charge - locked 9 hrs. For the BMS relearn.
Manual does divide those 2 things up.

So does the BMS start a relearn every time the vehicle is locked? Or is there something I need to do to initiate that relearn before locking the vehicle for 9hrs?

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[HeyBales]

So does the BMS start a relearn every time the vehicle is locked? Or is there something I need to do to initiate that relearn before locking the vehicle for 9hrs?

It does seem to at the next available chance. Probably wants a baseline for whatever it's testing.
I think resistance is one such value - combined with tracking age of battery from the last reset, that determines some charging strategy.
I have the logs that show when I did a BMS Reset on an old battery - it reduced the charging Amp rate for the next drive - which is what should happen on a new battery with less resistance.
Sadly my battery wasn't new and needed a higher Amp rate, I lost SOC% fast after that since my drives weren't an hour long for float charge ups. And my total external charge up wasn't held for that long.

Otherwise Relearn seems to be on a regular cycle of 3 days from my logging - because I lock nightly. This is when the Sleep period mA draw is a tad higher than other times.
Then again since I start about the same number of times daily also - it could be based on that, after so many starts.
Then again since so many of my drives are about the same length of time - it could be based on drive time, which means charge time.
Days and charge time makes sense to me.

I have confirmed that the SOC% is calculated on each startup after enough off time, with current temp and Voltage reading as big factors.
Haven't figured out the minimum time required to recalc, but usually if checking Voltage manually you need 2-4 hrs since last charging to get a valid reading.
But when checking manually nobody uses the formula for getting battery temp in there - which the BMS does know.

If you park and lock and regular basis - you'll get a relearn.
If not - do it for 3-4 days in a row.
If not - it's ready to do it at the next opportunity it finally is locked.

I'm beginning to think the Relearn is nothing more than a resistance reading, and deciding is the battery a SLA or AGM - since it does figure that out. Maybe it gets a test of amp draw - the manual says it'll do a known draw amount and check the results.

 

[mattbuilt1]

Settled with a 4 part solution for now:
1) Recharged the battery with a desulfating charger then ran a reset and relearn overnight.
2) Got the SSM updates to the ABS&ACCM done by our dealer. Still gets under my skin that they charge us our full deductible for updating a software problem that is acknowledged by Ford.
3) Added a cigarette port battery voltage monitor widget and a hitch brake light to trick the BMS into keeping our battery at 100%.
4) Turning off modem/wifi/etc and pulling the #11 fuse.

Going to hold off on installing the charger in the back seat so as to hopefully keep my mom's life simpler If the lighter widget starts showing low voltage, we can add more complexity.

 

[El Kabong]

I hear motors running when it's off just sitting there doing nothing/not moving

Normal noises. The moment you unlock the car it will do a bunch of power-on stuff (lots of relays clicking) and may also do the same when it's just sitting there off after awhile as it self-checks.

 

[Dad]

If I had a dollar for every time I dropped something. . .

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