The bottom row on my keyboard died suddenly

[caleb_land]

Hi,

The bottom row of my keyboard died today and I'm wondering what I should be looking for when I open it up.

Today I stepped away from my keyboard (a Keymacs with Matias switches) for 5 minutes and when I came back the bottom row of my keyboard wasn't working. I treat my equipment very well and there isn't any liquid damage etc.

I unplugged and replugged, refreshed the firmware, tried it on different computers with different cables with the same results.

I will open it up and look at it when I get the chance, but was wondering what I should look for on the PCB/microcontroller (which is a teensy Arduino separate board).

I appreciate any advice. I've never had this happen before.

-Caleb

[vvp]

There will one PCB trace (or wire if it is handwired) that connects all the bottom row switches which do not work. That trace does not have correct connection to an MCU pin or there is not a good contact to a pull-up or pull-down on that trace.

[Findecanor]

When this happens it is often a cold solder joint.
The solution is to take a soldering iron and redo the joint.

[DMA]

worst case you have a dead GPIO - in which case you'll likely need to replace controller. But yes, far more likely it's a bad solder joint.