A Dummy Discovers the Amazing Benefits of a B.M.S. Reset!

[Tbone289]

I’ll still never understand this. Years ago, late 70’s-early 80’s, I’d charge my car batteries +to+, -to-, On the battery itself, no + to +, - to frame. Even jump starting, same. I’m still here to talk about it!

Jump starting is the only real issue here. The theory is that during jump starting (high current), if the battery being jumped is in a poor enough state that it is off-gassing, the gas could cause an electrical arc across the battery terminals and explode.

In the case of charging the Maverick, going post-to-post just bypasses the BMS, which isn't really a problem. At least, not on the level of causing an explosion.

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[Mavster Mechanic]

since my truck went into deep sleep mode 22 hrs last saturday after i got the truck back from the dealer friday afternoon declaring my battery was good, and my brand new ancel battery tester said it was also good, i charged it to full last night (connected directly to the battery terminals) and tried the bms reset this morning. i never saw a flashing battery symbol, but after i left and locked the truck, the 12v powerpoint stayed powered (which it does not do in deep sleep mode). it's showing high 12s. i don't see how it can hurt anything. it's battery #2, a motorcraft 470CCA replacement that is 13 months old. time will tell.

Now that you charged your battery from grid power, try running your headlamps or at least parking lamps during every drive. This will likely "trick" the truck into keeping your 12v battery topped off.

 

[Meeka]

Now that you charged your battery from grid power, try running your headlamps or at least parking lamps during every drive. This will likely "trick" the truck into keeping your 12v battery topped off.

Will this work on an EcoBoost AGM battery cause I read here a week or so ago, been driving around with headlights on, not DRL’s, and no change!

 

[Glen Baker LLC]

Jump starting is the only real issue here. The theory is that during jump starting (high current), if the battery being jumped is in a poor enough state that it is off-gassing, the gas could cause an electrical arc across the battery terminals and explode.

In the case of charging the Maverick, going post-to-post just bypasses the BMS, which isn't really a problem. At least, not on the level of causing an explosion.

Yeah the above is something I would not want to happen especially inside the cab of the truck!!

 

[HeyBales]

Will this work on an EcoBoost AGM battery cause I read here a week or so ago, been driving around with headlights on, not DRL’s, and no change!

No change to what?
The voltage in the morning?
Voltage while driving?

The other thread shares several experiences that if your battery is already undercharged enough - the method doesn't work for hybrids.
Battery needs to be new or fully charged.
Then BMS is willing to keep it charged up.

It would be interesting for an EB to report on using the method too - would need a scan tool and some readings, and new/charged battery.

 

[Meeka]

No change to what?
The voltage in the morning?
Voltage while driving?

The other thread shares several experiences that if your battery is already undercharged enough - the method doesn't work for hybrids.
Battery needs to be new or fully charged.
Then BMS is willing to keep it charged up.

It would be interesting for an EB to report on using the method too - would need a scan tool and some readings, and new/charged battery.

Chill, both! I’m not a newbie!!

 

[DS_Ohio]

Since the BMS Relearn isn't a nightly thing (still can't decide if a time or mileage type cycle) - it was probably sitting on an old SOC% after they did a recharge, and low enough it did DSM for modem.
Now the battery saver functions for lights/power port are Voltage based, so in theory that could be above 12.1V while the SOC% is on a delayed effect.

Curious what your Resistance reading was on 13 months old?

Perfectly fine charger hookup. Truck doesn't log Amp hours of charging anyway with key off.
And that would be a mistake if it did. Then it would charge less while driving.

i've tested it twice. 5.52 and 5.38 milliohms.

 

[Cherokee]

Yeah, but damn, I am old and find navigating that book a bit frustrating. Not impossible but damn close to it I'll tell ya. Someone here recently suggested that it seems to be organized and written with a digital copy assumed. I can see that, a search bar would be great.

Case in point, and mind you it could be me, but a while ago I wanted to look up Cargo Lights. Go to "C" and there is nothing under C for Cargo Lights. Now I am sure it is somewhere, of course. At that point it was just quicker to hit up google and keep that book on the shelf.

Youngers wrote the manual. They don’t know the proper way to organize anything.

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