Symptom: Random disabling of a column or key spam of that column.
Would you guys agree that it must be a faulty MCU soldering?
I just want to make sure that there is nothing I can do before looking for a specialist that can fix MCU soldering.
That or shorting to the case or shorting from screw in stabilizer. Test without case or stabilizer screw to be certain.
Thanks, will do. But to be clear - only contacts within this specific column should be tested? E.g. stabs belong to another column, so no point in uninstalling them?
That doesn’t sound very likely at all.
Does it happen when you’re typing on it only, or if it’s just sitting there as well?
Both, when typing and when idle.
I believe there is a short if it happens when idle. Probably not the MCU. Unless there is a blob of solder bridging pins on it.
A guy in discord described the same issue. He said that reflowing MCU soldering solved it. That’s why I’m thinking that.
edit: However I am also lack experience with soldering. So even though it looks fine, I am not too certain about it.
post a close-up photo and perhaps we can spot the issue on the MCU
The MCU looks just fine, but my soldering right under the LEFT inscription looks the most wanky. I guess I thought those pads are connected anyway so that blob is no biggie. Think this may be the problem? (it is the 4th column that gives me troubles, the one under the inscriprion)
Did you unscrew that stabilizer to test it? I’ve had a pcb short before where the screw didn’t look like it was touching a pad (I guess there was a small trace running very close to the hole that was almost invisible to the naked eye)
You could start by desoldering that switch, I guess.
It looks like there is a fair amount of burned flux on the pads right now. I think either your tip is too hot, too large, or you are holding it on the joint for too long.
If you plan to desolder or reflow the chip, you might want to pick up some liquid flux. A flux pen Is an easy and helpful tool to have.
I will take off stabs, tape out OLED and run with no or low RGB and will see if anything changes.
It’s a 30W iron, held it for ~3 secs, so it should be OK. However, my technique had its flaws, and I did some minor damage to some of the switches that I had to fix later.
Will report in a week or so.