[The Notorious Flank Sucker]

Apologies for posting in this section, apparently I don't have permission to post it where I thought it belonged in the Doctor's Corner.

I have an 11.1V lipo that I can't balance charge. I got it second-hand and don't know anything about it's history. My Hitec X1 AC charger gives me a 'balance connector error' when I connect it and try to balance charge. I can normal charge it (non-balance), but the pack begins to swell pretty quickly so I have to stop.

I've put my multimeter on the end of the balance connector, with the ground probe attached to the pack's ground terminal and this is what I got:

Red wire (cells 1, 2 & 3): 9V
Blue wire (cells 1 & 2): 4.5V
Yellow wire (cell 1): 0V

I unwrapped the top of the pack to get at the wired connections on the PCB. Even touching the probe directly to the yellow wire's connection on the board gets a 0V reading.

So here come the newb questions:

- is cell 1 dead?
- …and if so, does it make sense that the other cells are reading 4.5V each?
(I originally assumed 9V across all 3 cells meant that each one was reading 3V, so the cells must be fine and there's just a connector or wire problem.)
- …and if not, what's likely going on?
- what's happening when I regular charge the pack - are the two 'good' cells getting overcharged and causing the swelling?

Any tips or guidance greatly appreciated!