Water damaged Corsair K95 RGB Platinum - replaced switches, no improvement, what

[wilko23]

I spilt a bit of water on my keyboard a few months ago. It worked fine at the time, next day several keys were dead - F6, 6, Y, H and B - all in a line.

I dried it out and months later there's no improvement.

I didn't notice any damage at the time, but I thought I'd try swapping in some new switches - for 6, Y H and B - not F6 as that was hidden by some other PCB and plastic.

After the new switches are in and the LEDs still work, and from what I can tell and test with a multi-meter there is still current going through the replaced switches.

I didn't swap the F6 key as I didn't realise it was broken, it was hidden by a plate which I've just removed and it looks like the PCB is damaged there.

Given this is a £180 keyboard which I can't replace right now I'd love to fix it.

Can anyone provide some ideas on what I should do next, or if the PCB holds any clues as to what I should do?

I've taken some pics and a video showing off the damage you can see here - https://imgur.com/a/5MGZwdL

N.B. The video is taken after I did some more cleaning. I've just ordered some more Iso as I ran out so I can clean it more thoroughly.

[russeree]

I don't have the schematic for the K95 but those seem like that would all share a vertical trace. Check diodes and clean contacts at the microcontroller.

That would be my 2 cents.

[pixelpusher]

I spilt a bit of water on my keyboard a few months ago. It worked fine at the time, next day several keys were dead - F6, 6, Y, H and B - all in a line.

I dried it out and months later there's no improvement.

I didn't notice any damage at the time, but I thought I'd try swapping in some new switches - for 6, Y H and B - not F6 as that was hidden by some other PCB and plastic.

After the new switches are in and the LEDs still work, and from what I can tell and test with a multi-meter there is still current going through the replaced switches.

I didn't swap the F6 key as I didn't realise it was broken, it was hidden by a plate which I've just removed and it looks like the PCB is damaged there.

Given this is a £180 keyboard which I can't replace right now I'd love to fix it.

Can anyone provide some ideas on what I should do next, or if the PCB holds any clues as to what I should do?

I've taken some pics and a video showing off the damage you can see here - https://imgur.com/a/5MGZwdL

N.B. The video is taken after I did some more cleaning. I've just ordered some more Iso as I ran out so I can clean it more thoroughly.

You show some pretty solid evidence of scratched/broken traces in the first photo.  Did you try to repair these?  This kind of mark can easily break a trace.




Also, those pads where you swapped out the switches look pretty rough.  You probably need to use rosin core solder or more flux and turn the heat down on your iron for future repairs.

[wilko23]

I haven't tried anything beyond the switch swapping yet.

I'm a newbie when it comes to PCBs and keyboards - this is my first MK in fact. I've only successfully repaired a hard drive before by soldering.

How would I go about reparing these? In my reading I came across someone mentioning circuit repair paint - is that what I should use? Or what's the correct terminology I can use as a starting off point?

[pixelpusher]

these look small, but there could definitely be a break.  I would scrape off a small bit of solder mask on the trace on either side very carefully with a razor blade... light scraping, no cutting, hardly any pressure.  These look small enough that if there ways a break there, you could drag solder to bridge it.  Just put a dab of flux on the trace, get some solder on the end of your iron, and drag it across to bridge any breaks.  They sell flux pens for fairly cheap on amazon if you don't have one.  Flux paste is okay if you have that, but you'll need to clean it up afterwards with some isopropyl

This may not be the issue, but it's a starting point.  Unless you are able to follow those traces through their VIAs and figure out if they are still intact.

[wilko23]

Thanks. This is helpful. Just so I'm 100% clear - the solder mask is the green stuff and I'm scraping that off to get to the copper on the board that's part of the circuit? Once I've scraped (to expose the circuit?) - I should be able to test with a multi meter if it's broken too? (to confirm before soldering)

[pixelpusher]

Thanks. This is helpful. Just so I'm 100% clear - the solder mask is the green stuff and I'm scraping that off to get to the copper on the board that's part of the circuit? Once I've scraped (to expose the circuit?) - I should be able to test with a multi meter if it's broken too? (to confirm before soldering)

yes, the green stuff is the solder mask.  In that photo, the light green lines on the PCB where I've circled are copper traces that are covered with a green material called solder mask to protect them and to keep the traces from coming into contact with anything that might conduct electricity (or allowing solder to melt to them, hence the name "solder mask")