I would connect -C and charge it a bit, the BMS might be in some protection mode…that might release it
Charge it by how much ? I will try it
Wow nice catch @scepterr I didn’t even notice his -C wasn’t connected. You could be right about the BMS in a protection mode, as if he’s not changing via -C it may not ever be hitting balance kick off - which could lead to an Imbalanced pack putting the BMS in protection mode
@ElskerShadow have you measured the volts of each series group yet to verify balance?
Unfortunately i’ve been busy AF and couldn’t find the time to grab a multimeter i ll buy one on amazon prime so i’ll have it tomorrow. But i have to admit that i d like to find an easier solution because the pack is completely taped/ sealed it’s gonna be a pain in the ass to remove all that
But my last BMS ( wich was the same ) had no wire connected to -C, wich cable should be connected to -C ? there’s only two connected to the PCB not including balance leads
You don’t need to remove the tape to check the cells…just check the voltage at the JST connection
-C is for the negative side of the charger plug
Measure from the backside of the balance JST legs on the BMS… No untaping involved
Plus not having a multimeter and building batteries… Seems silly don’t ya think 
B- is connected to the XT90 out and P- goes all the way back to the bottom of battery
My negative charger lead goes into this tiny BMS i dunno what it does
So should i still move the p- into c- if it’ not the charging ?
Um
-B goes to the battery negative terminal -P goes to the xt90/whatever connector to your load.
You’ve wired it backwards
I’m so confused why do you have two BMS…
Lol
The way your big BMS should be wired
Postive from charger jack to positive battery terminal Negative charger jack to -C on BMS Postive battery terminal to xt90/barrel out -P (negative of the postive out) to xt90/barrel out -B to battery negative
Vs what you have now -some random extra BMS for charging??? -big BMS has -B and -P backwards
In dunno it’s always been like that, one Bms with white balance and a tiny BMS with red balance…
So maybe if i switch B - and P- it will be good tho ?
To me it looks like you can remove the tiny one with red balance.
And then just stick the negative side of the charger plug to -C on the other BMS
And reverse the -B and -P
If you didn’t build the board…it looks like the person who did didn’t have the concept that a single BMS can be used for charging and discharging…
I built the board just i had to buy the battery, it’s from eskating.eu and built in china I think
Also your positive side of the charger is connected to the -ch on that second BMS with red balance wires…
I think you have alot of things backwards…and possibly shorting…
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Apprently the tiny bms is for LCD readout
I hope nothin is shorted
I will try now what you say
Positive charger cable goes directly into battery it’s normal ?
Big cable : goes back to battery Litle cable : negative charge input
I just did what you told me, SWapped B- and P - and switched black charging cable to C- now the battery won’t turn ON.
Sorry was looking at your last pictures this one is what I was coming confused about
This is how I would have wired it
Right now it’s wired like that and no power at all
I’m beyond confused with your wiring and multiple BMS lol
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Believe me you can’t be more confused that I am now