I got a battery 12s2p 30q in march or april and it worked
i didn’t use it since then and now it’s neither charging nor discharging
smartbms is part of the assembled battery
unity was disconected
i have no multimeter handy to check out voltage
any ideas?
Have you checked the bms readings?
how to with no power for bluetooth/multimeter…
I’d really recommend you spend $10 on a multimeter. Otherwise there’s no way to check anything. At least not safely… There’s always the lick test. 
(Don’t lick the battery)
Pics?
You plug it in and the charger shows it’s full? Like the green light? Green is usually charged, red is charging . Is that accurate?
Really you need a multimeter. No way around it
I got mine for like $18 from Walmart and have had it for years. It’s probably shit but it’s done everything I’ve ever needed it to do reliably. They sell ~$10 ones too.
Get a multimeter, and be super mega careful not to short the battery when checking voltage
paging @pjotr47 for diagnostic aid
Not to mention being super careful when cutting open. Best to let the builder walk you through that process
you know what? before you start telling anyone what to buy you need to get yourself some calipers lol 
For quick voltage check you could just connect the unity and check the voltage reading via app.
As you mentioned the pack has a smart bms installed,
the bt module needs energy (is switched on) as long as the balance wires are connected to the bms (and the power wires to the bt module for sure).
Likely that the standby mode of the bms fucked up your battery.
You have a pm.
I use my multimeter almost everyday.
I use calipers twice a year.
I’d rather buy another multimeter before calipers
I use my calipers almost everyday.
I use a multimeter twice a year.
I’d rather buy another caliper before a multimeter
Get you some calipers that can measure multiple meters!
Then you’ll be all set 
