Hi, I didn’t charge on time after riding and one group not charging and near 0
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You should stop using that battery immediately, do not charge or discharge it, and contact a place where it can be disposed of properly.
Alternatively, if you want good advice, this is possibly a broken balance lead and not a fire hazard. If you are able to, you can open the battery and probe around to double check the cell voltages with a multimeter. Knowing what type of pack it is will be helpful
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evwan is on the right track here, and techshit comes off as dramatic but has your safety in mind. i think. defiantly needs to get fixed before you ride it but not the end of its life yet. if you look at the total voltage and divide it by 12 you get 3.74v… this is a bad sign but only one sign. this means that the total pack output voltage does not align with it being a bad sensor. depending on how your battery is made and how testing goes you might be fine or you might need to make this an 11s battery to use it further.
You need to manually test the voltage at the battery output and record it with the time date.
then carefully test the voltage at the balance header and record this also.
you should also unplug the battery 100% from everything right now so there isn’t any further drain just incase. accidentally drawing from the battery could damage it in this state so no testing to see if it runs 
do not charge anything else until you have this all sorted. also good advise is to check a neglected battery before you charge it. if its been sitting and possibly drained a group too low then is the time that it can be assessed and fixed accordingly… after you plug in a charger many other things can happen to have a bad day. we don’t like bad days here.
post everything and also add some photos of the battery so people can get an idea of how its put together and offer some advise.
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You guys make a lot of unsafe assumptions.
If OP is technically inclined, sure, but I’m not assuming that.
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all good man, op is here to get some advice. most people on this forum get up to speed or find out where they should put their limits pretty quick, lets sus it out and help the best we can
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thanks for reply, before I see this I ride it maybe 10km and now when plugged to charger doesn’t charge. actually 2 days ago I ride it in the rain and water get in and I cleaned it but now i will open it do what you said.
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Just to clarify, you mean 11S correct? Removing 1 (assumed bad) p-group?
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That’st not good; it could be anything at this point. Maybe something shorted on that one p-group and hence zero volts. Or it could just be a broken balance lead. The only real way to find out is to inspect the pack.
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Words hard, thank you 
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I agree with advice here pretty much. Opinions run stronger regarding batteries than most other subjects because they can cause fires, as well as the condition and aging of a battery be difficult to determine so often people assume the worst, which is fair.
If those cells are below 2 volt, I wouldn’t trust them at all. Between 2 and 2.7V, still a risk of fire but less risky in my experience (I’ve only used recycled cells from batteries in various conditions). You do need to check the groups with a meter. That’s where I would always start anyway.
The reason for not charging a flat li-ion, is that a reaction happens below about 2.5V which causes dendrites to form. Initially, this may cause a higher rate of self discharge, which is a warning sign. I once declared a battery as scrap metal, but the fella went against advice and charged it anyway. It took some charge, until one cell, assumingly, shorted out completely and instantly discharged the adjacent cells through it and caught fire.
I’ve also seen BMS report wrong voltages on P groups (last owner likely cocked up calibration), another reason to always check cells with a meter.
Speaking of meters, my old faithful fifteen years of daily use meter died two weeks ago. Resoldered all the components and she’s away again. Sometimes you get lucky, hope you’ve just got BMS problems.
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is that worth working on it with multimeter
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No mate that is fucked 
you need to find a place to safely dispose of that
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Ya, sorry that’s toast. Don’t keep it in a house where people sleep. That needs to be replaced and recycled. That’s probably the worst state ive seen a battery in a long time. 
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I reiterate my initial advice.
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The battery was not known to have been ridden in the rain until several posts in.
It could have easily been a broken balance lead, and a few minutes with a soldering iron repair, with the limited info initially offered.
I’ve partially torn down my unintentionally submerged pack.
The fishpaper was still damp, two months later, slightly swollen, and super fragile.
I wonder how high humidity alone, affects its electrically insulative, and abrasion resistance qualities.
The Tesa and Kapton tape and their adhesive were in excellent condition.
The Tesa tape in a survival situation, could have been reused.
A wet battery is a bad thing, and dangerous, I just wonder if fishpaper’s sponge like qualities, makes it worse
you get no points for guessing correctly, as on the spot as it was 
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