Column of RK84 Stopped Working & Adjacent Keys Are Logged

[questionableaverage]

Hello,

As title suggests, my RK84 keyboard's column has completely stopped working (characters: F10 0 P ; ? CTRL). No keys are logged when I press on any of the keys on said row. I'm assuming (?) no current is flowing through it since the LEDs do not light up.

Using the continuity setting on my multimeter, the traces (?) appear to work perfectly fine down the column. Same goes for the diodes. I did what I saw online and made a jumper between two points across the row (see below). This made the non-working column LEDs to light up.

https://imgur.com/a/P6XP8YH

HOWEVER when I type anything using the keyboard, I get the adjacent character that I attached the jumper cable to (EG: If I jumped the non-working key to the right, I wouldn't get the letter 'P' I would get '['). I'm not sure if this is an unrelated issue or if I did the jumper cable wrong, but I'm completely stumped at the moment.

I consider myself quite a noob when it comes to Mechanical Keyboards (and even more so with anything electrical), so any help would be appreciated! I don't mind learning anything new, but I will (probably) ask some stupid questions because I'm generally unknowledgeable. Thanks!

[suicidal_orange]

I can't make out most of the traces and it's never good when the LEDs are linked to the switches but the easiest option would be to try the jumper the other way ( ; to L) which will fix it if the board uses U shaped "columns".

If that doesn't work please take a pic with more light which will show up the traces better and should speed up the camera to make it sharper too

[questionableaverage]

Hello! Thanks for replying. Unfortunately connecting L and ; didn't work either: this time what was supposed to be the ; key started to output L when pressed. Honestly I'm not too sure as to what that problem is with this keyboard, since I haven't seen anything like this before so I don't think I can be of much help.

However, I did manage to take some better pictures of the PCB. https://imgur.com/a/oox2UCG

If I still need more zooming in with the pictures, please let me know. Thanks otherwise. ^_^

[questionableaverage]

I can't make out most of the traces and it's never good when the LEDs are linked to the switches but the easiest option would be to try the jumper the other way ( ; to L) which will fix it if the board uses U shaped "columns".

If that doesn't work please take a pic with more light which will show up the traces better and should speed up the camera to make it sharper too

I think I was supposed to click reply. Oops! Anyway, I did as you said in my comment above.

[questionableaverage]

Update: Not sure if this is relevant or if it's just a fluke on my part, but after playing around with the continuity, I noticed that there was no continuity between the non-working column and what I assume is it's given pin on the black chip. Assuming the pattern, it appears that all other columns have continuity with the black chip except for the dead column. (BUT this only happens if I remove the jumper cable.) Again, not sure if this is the problem.

[suicidal_orange]

Don't worry about officially replying, I don't have notifications on!

Yes every column has to link back to the chip, if you add a jumper you connect it to another column so it will have continuity to that column's pin instead.  Looking at the new pics it's clearly a commercial board not one designed by someone in the community (read: it's a mess), the columns are connected as expected and the LEDs are on the same trace but it has 3 pin diodes which, at least sometimes, connect to two switches.

Find something pointy (a needle or thin piece of wire) plug the board in and short the yellow pad to the pin you think it should be connected to on the chip, I think it should be one on the bottom of the chip near the trace I've coloured in (green being definite and red not) and if it types ? be happy.  If it does you'll need to find somewhere along the trace to scrape off and solder to (unless you're an absolute pro and fancy soldering to the tiny chip leg!), if I've got the right trace in the orange circle would be a good spot as there are no traces right next door.  If you need help with that post a pic with the pin highlighted and I'll have a look

[questionableaverage]

Hello!

Thanks so much for the advice you gave! I ended up managing to fix the keyboard by making a jumper between the pin of the controller and the left side of a key on the non-working column (attempting to connect the wire with the PCB didn't work unfortunately). I was worried about soldering it since (as you said) it is a very precise point, so I ended up just attatching it with electrical tape. That seemed to have done the job since the keyboard now works! Thank you so much for your help.