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geekhack Community => Keyboards => Topic started by: foonone on Sun, 31 January 2021, 11:15:49

Title: Keychron k2 starts spamming a row of letters after soldering
Post by: foonone on Sun, 31 January 2021, 11:15:49

Hi @ all

did i just killed my keychron pcb?

After installing new switches i had a spamming of :" agh'ashj\sj;LKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLKLK "

is there a way to fix it?

Best regards from Germany

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: suicidal_orange on Sun, 31 January 2021, 11:27:05

I see missing pads on the two switches just off the bottom left corner of the big white printed box, doesn't look like they should be linking back to the controller but if they are that could be the problem so try linking those two to the lower pins of the switch either side to complete the row circuit but if they need to connect to something on the other side you'll not have much luck (unless you can see what's going on on the other side through the plate)

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: yui on Mon, 01 February 2021, 06:22:17

to me looking at it quickly it looks like a short, as usual i do not know that flux you used but as some of them are conductive i would recommend cleaning it, and also check for solder bridges around the middle row, and especially near K and L

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: foonone on Tue, 09 February 2021, 06:50:47

first of all sorry for my late answer!
and thank you for your quick replies!
finally i had some time to desolder all switches. found at least one damaged / broken pad?
i guess its rip for the keychron then.

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: suicidal_orange on Tue, 09 February 2021, 07:12:18

If you've desoldered all the switches please take some nice photos of both sides (if you can, it's a black PCB so not easy)

It is fixable with just a couple of wires (if that is the only damaged pad, a few more if there are more) but working out where they need to go is tricky.

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: yui on Tue, 09 February 2021, 07:22:46

it never is the end, unless you want it to be, and i am guessing you do not :)

Title: Re: Keychron k2 starts spamming a row of letters after soldering
Post by: chromov113 on Tue, 09 February 2021, 08:17:19

Quote from: foonone on Tue, 09 February 2021, 06:50:47

first of all sorry for my late answer!
and thank you for your quick replies!
finally i had some time to desolder all switches. found at least one damaged / broken pad?
i guess its rip for the keychron then.

If I was you, I would continue troubleshooting, just of curiosity. Did you try connecting a PCB without switches to a PC?