Author Topic: The same keys on my PCB are not working again after fixing it?  (Read 1723 times)

0 Members and 1 Guest are viewing this topic.

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카

So I posted a few days ago about this issue on r/mk. I just built my first soldered keyboard (Stellar65) at a local soldering workshop/class, and the first time I tested it, everything worked fine. I brought it home and the entire third row, as well as the ď\|Ē and Pgup key stopped working. I posted a photo of the pcb and someone pointed out it could use more solder. So I added more, and tested it again and everything worked.

Iíve been using this board for a few days without any issues. Now suddenly the same exact keys are no longer working again. The only thing I did before they stopped working was unplug the board and I took off my space bar to readjust it and put it back on (now I regret doing that lol). Iím very confused on what the issue could be. Why are the same exact keys working, then not working, then working again, then not? Iím brand new to soldering/troubleshooting, so I donít have any tools like a multimeter to find out the issue. Any tips or ideas would be great :(

Photo of the pcb (before resoldering) https://imgur.com/gallery/7Y4pSJi
Photo of the keys that keep dying https://imgur.com/gallery/ZdNQboI
Q2hyeXNhbnRoZW11bQ

Offline suicidal_orange

  • * Global Moderator
  • Posts: 4397
  • Location: England
Re: The same keys on my PCB are not working again after fixing it?
« Reply #1 on: Tue, 01 June 2021, 06:44:35 »
Sounds like you have a problem with the connection from that row to the controller chip.  Usually you can check in the firmware what's connected to what but this doesn't seem to be included in QMK and VIA, while friendly for programming, is a bad thing when it goes wrong.  The other option is following the traces but it's a black PCB and I can't even be sure if the diodes or non-diode pins are connected across the rows, the only possible clue is D26 being in a strange position with an extra trace which looks all kinds of wrong, but that in itself doesn't say much.

You could ask the vendor/GB runner/whoever for a schematic or pinout or the QMK firmware, if that fails your only option is carefully poking the pins on the chip shorting them to a switch until you get the desired outcome.  I can help with that but hopefully you don't need to.
120/100g linear Zealio R1  
GMK Hyperfuse
'Split everything' perfection  
MX Clear
SA Hack'd by Geeks     
EasyAVR mod

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #2 on: Tue, 01 June 2021, 12:56:19 »
Usually you can check in the firmware what's connected this doesn't seem to be included in QMK and VIA

If it helps at all the name of the pcb is Nebula65, I tried looking up the board too as Stellar65 and it didnít show up. Since I have no idea how to any of the stuff you just described lol, Iíve been in contact with the vendor as well so hopefully I can figure out whatís going on :( realllly donít want to desolder everything if I donít have to... :-X
Q2hyeXNhbnRoZW11bQ

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #3 on: Tue, 01 June 2021, 14:14:34 »
Sounds like you have a problem with the connection from that row to the controller chip.  Usually you can check in the firmware what's connected to what but this doesn't seem to be included in QMK and VIA, while friendly for programming, is a bad thing when it goes wrong.  The other option is following the traces but it's a black PCB and I can't even be sure if the diodes or non-diode pins are connected across the rows, the only possible clue is D26 being in a strange position with an extra trace which looks all kinds of wrong, but that in itself doesn't say much.

You could ask the vendor/GB runner/whoever for a schematic or pinout or the QMK firmware, if that fails your only option is carefully poking the pins on the chip shorting them to a switch until you get the desired outcome.  I can help with that but hopefully you don't need to.

& now itís working again! Iím using it to type this right now. It has to be a connection issue then? I really hope it doesnít do this again  :'( maybe as long as I donít mess with anything lmaoo. Iím using the keyboard on my iPad with a usb dongle, it might sound silly but just throwing that factor out there. Donít know if that could also be causing the problem. Haha
Q2hyeXNhbnRoZW11bQ

Offline suicidal_orange

  • * Global Moderator
  • Posts: 4397
  • Location: England
Re: The same keys on my PCB are not working again after fixing it?
« Reply #4 on: Thu, 03 June 2021, 07:08:53 »
The Nebula68 is in qmk so we're good to fix it if it breaks again.  Hopefully not :)
120/100g linear Zealio R1  
GMK Hyperfuse
'Split everything' perfection  
MX Clear
SA Hack'd by Geeks     
EasyAVR mod

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #5 on: Mon, 14 June 2021, 03:55:35 »
The Nebula68 is in qmk so we're good to fix it if it breaks again.  Hopefully not :)

I was able to speak with the person who made the PCBs, and identified that it was due to one of the chips on the board not having enough solder. They told me to add more to it, but because of my lack of experience & the pins on the chip being soooo tiny, I added solder & it fixed the row that wasnít working, but in return I screwed up the rgb because I added too much. At least I know now it wasnít because of anything I did lol
Q2hyeXNhbnRoZW11bQ

Offline suicidal_orange

  • * Global Moderator
  • Posts: 4397
  • Location: England
Re: The same keys on my PCB are not working again after fixing it?
« Reply #6 on: Tue, 15 June 2021, 04:03:21 »
Yeah, SMD controller chips are not fun to solder to.

You could heat the solder then drag a pin or needle between the now bridged pins to clear it, might take a couple of swipes.  Or if there's a big blob of solder you could get some desoldering braid and remove it, you wont suck the solder from under tightly packed SMD legs.
120/100g linear Zealio R1  
GMK Hyperfuse
'Split everything' perfection  
MX Clear
SA Hack'd by Geeks     
EasyAVR mod

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #7 on: Sat, 19 June 2021, 00:34:39 »
Yeah, SMD controller chips are not fun to solder to.

You could heat the solder then drag a pin or needle between the now bridged pins to clear it, might take a couple of swipes.  Or if there's a big blob of solder you could get some desoldering braid and remove it, you wont suck the solder from under tightly packed SMD legs.

Soooo this is the longest my keyboard has worked, itís been almost two weeks! And now the same keys, again, stopped working. This is the 7th time Iíve taken apart the board I really just donít wanna deal with the chip anymore ahhh! Haha :confused:

My main question is, what could be the cause of these same keys to stop working, even though theyíve been functioning fine for all this time? I bought myself a desoldering wick so I will try to attempt to remove the access, but itís still a bit strange how finicky this has all been! Thanks again for your replies and input.
Q2hyeXNhbnRoZW11bQ

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #8 on: Sat, 19 June 2021, 01:33:32 »
I heated up one of the pins as directed again & when I tested the faulty row, all of the keys on that row now register the key + the key diagonally above it. For example pressing L would register as ďOLĒ or H as ďYHĒ.

Just great :(
Q2hyeXNhbnRoZW11bQ

Offline suicidal_orange

  • * Global Moderator
  • Posts: 4397
  • Location: England
Re: The same keys on my PCB are not working again after fixing it?
« Reply #9 on: Sat, 19 June 2021, 11:42:09 »
That sounds like you now have a short to the pin on the other side of the one you're trying to fix, not fun but not as bad as it looks.
120/100g linear Zealio R1  
GMK Hyperfuse
'Split everything' perfection  
MX Clear
SA Hack'd by Geeks     
EasyAVR mod

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #10 on: Sat, 19 June 2021, 12:51:58 »
That sounds like you now have a short to the pin on the other side of the one you're trying to fix, not fun but not as bad as it looks.

Would removing the access help in anyway? Iíve been back & forth with the person who made the pcb and they said it could be because there is not enough solder it cracked?
Q2hyeXNhbnRoZW11bQ

Offline suicidal_orange

  • * Global Moderator
  • Posts: 4397
  • Location: England
Re: The same keys on my PCB are not working again after fixing it?
« Reply #11 on: Sat, 19 June 2021, 15:49:07 »
You need the right amount of solder to make a good joint under each pin but none connecting two pins.  If you remove the excess with wick that's exactly how it should finish up.
120/100g linear Zealio R1  
GMK Hyperfuse
'Split everything' perfection  
MX Clear
SA Hack'd by Geeks     
EasyAVR mod

Offline Madzuka

  • Thread Starter
  • Posts: 25
  • 메즈카
Re: The same keys on my PCB are not working again after fixing it?
« Reply #12 on: Wed, 21 July 2021, 23:39:13 »
You need the right amount of solder to make a good joint under each pin but none connecting two pins.  If you remove the excess with wick that's exactly how it should finish up.

I did that but for some reason but it still did not work, so I sent it in to spacecables a couple weeks ago to have it repaired after Yiancar tried his best to give me tips to fix the faulty chip on my own. I finally just got it back today, was so excited to use it but itís still faulty..... the V,G,Y & 5 keys register with the key next to it ďvb, gh, ty, 56Ē & vice versa.

I guess that means they are shorted? Not sure, Iím just so over troubleshooting this pcb, itís been over 2 months of this now.. I would think theyíd test the pcb before sending it back to me, thereís also a crack in the plate when it wasnít there before I sent it to them. Not really sure what to do now :( Itís my first time soldering a keyboard so I donít have desoldering equipment either, to just ask for a replacement pcb. This fault isnít even because of my beginner soldering skills, if the controller chip wasnít faulty it would be working just fine right now! Gah, just ranting now Iím super bummed.
Q2hyeXNhbnRoZW11bQ