Posting this in case it helps someone with the same problem
I got a HS60 v3 and fried it after less than 3 days because I was using a metal case without proper insulation between standoffs and PCB. The whole 6/Y/H/B/spacebar column was dead. Resetting the board did not help.
I revived it using the following method
Image:
https://imgur.com/a/EyW89hc- Take a multimeter. Looking at the pcb on the bottom side, make sure there is continuity between the RIGHT socket of each key in the dead column and the old pin (3rd pin on the top left of the chip, see image). If there is continuity, it means the pin is fried. If there is no continuity, you have a different issue, like a scratched trace somewhere.
- Solder a short wire from the RIGHT pad of the spacebar socket to the exposed A6 pin hole (see image). Check with the multimeter for continuity between all the RIGHT socket of each key in the dead column to the new pin.
- Using a very sharp xacto cutter VERY CAREFULLY cut the trace from the column to the old pin. This took me a while to find, and I think the best place to cut is (see image) right after the via hole near the spacebar socket. Scratch on top of the trace and expose some of the copper, then test for continuity with the old pin, just to make sure you're cutting the right trace. Then keep going with the cutter until there is no more continuity to the old pin.
- Download the qmk_firmware repo and open this file -> keyboards/hs60/v2/ansi/config.h
- change the line
#define MATRIX_COL_PINS { A13, A10, A9, A14, A15, B8, B9, C13, C14, C15, A0, A1, A2, A3 }
and change B9 to A6.
- Flash firmware on the board. FYI this is done from the root of the qmk_firmware directory and executing "make hs60/v2/ansi:via:dfu-util"
Btw I have the v3 ANSI version. The traces might be different on ISO and HHKB versions