Touch Screen unresponsive after flex cable installation

[Coaltergeist]

I'm currently working on a capture card installation for a New 3DS LL, and I've installed the screen flex cables and soldered the audio cable with no issues. I've triple checked everything and it's all seated properly; however when I go to turn on the system to check functionality, the touch screen is completely unresponsive. Everything else works; the buttons all work and the touch screen itself has video (audio is fine too), but when I press the screen with the stylus or my finger, I don't get any response, regardless of how hard I press. I took everything apart completely and reseated everything, and triple checked everything again, but still nothing. Any ideas?

[Coaltergeist]

I've done a lot of research and I'm fairly certain it's the touchscreen digitizer. There's probably some dust or grunge between it and the shell. I don't have the tools to replace it right now but I ordered some and will attempt to fix/replace the bottom lcd over the weekend.

Wish me luck

[Coaltergeist]

So I'm really stumped here; honestly I have no clue what the problem is. I downloaded a button test program to see if I could get an idea, and it was showing that the console is registering a continuous bottom-right input from the circle pad, even with the circle pad removed. I replaced the touchscreen AND digitizer, but no luck (cleaned the housing too in case of dust). Anyone have any ideas? Here are some pictures of the installation: https://imgur.com/gallery/QY5YCBt

[Coaltergeist]

Well everyone, I figured out the problem; figured I would at least post it here in case anyone else ran into something similar. Basically there was a microscopic solder blob on a smd component by the audio flex (you can actually see it in one of the pictures I took, that's how I found out), and when I melted it off, everything worked fine. Somehow the solder blob was shorting something, or something was being pressured, I'm not sure what exactly, but I think the result was that the touchscreen was registering a continuous input, and that was locking up the circle pad as well. Everything's working fine now, and the capture card is installed successfully.

[Dreamdreads]

Hello, I came across your post and I have the same problem!
I checked the flexible and even removed it, I can't get the use of the touch screen back. an idea ?

here is a photo of my motherboard https://imgur.com/a/Pa7wY1f

[Coaltergeist]

It looks like you don't have any solder bridges; when I was researching my problem I found a few things to check:

• do you have a screen protector? The screen protector can sometimes jam in between the shell and the screen and mess with the touchscreen

• is there any dust on the screen? Sometimes dust can get between the screen and the console and have the same effect. I would recommend taking the entire touchscreen out and cleaning everything

• is your digitizer intact? Check the digitizer connector; it's the 4-pin flex cable at the top/center of the motherboard, to the left of the touchscreen flex cable you installed the capture card to. If you're digitizer looks broken you might have to replace it; it's pretty inexpensive on Amazon

Good luck; I hope you figure out what the problem is!

[Dreamdreads]

Thank you for the different avenues to follow, I found it! It's the digitizer that is HS, I connected a digitizer from a 2DS HS that I had left and it works! I ordered a new one. Thanks to you !

[Coaltergeist]

Glad to hear it, hope everything goes well