Hardware Switch MicroSD slot not working

[AlexMCS]

Hello everyone.

After my switch suddenly stopped booting Hekate, analyzing its debug messages, it seemed the issue rested on my microSD/SD slot reader.
Using a USB adapter, I can read the microSD normally (it's a 256GB one from Samsung), and it worked flawlessly before, so I assumed it was the microsd reader (HAC-SD-01) gone bad.

Bought a new one, replaced the old, and then, with the Switch still open, tested it. Hekate booted ok. Nice.
Then after closing the mains 4 Y screws of the switch back, I tested it again. This time, Hekate booted, but all the text looked like gibberish, with squares instead of letters and so did the images, they didn't load correctly.

After shutting the switch down and back again, I'm back to the previous error message: microsd not loading.
Using other payloads (such as memloaderv3) give the same response.

I've seen a few topics about faulty microsd readers here, and found nothing seemingly wrong with the slot on the main board, and both my reader units seemed fine.

Now I'm worried something is simply damaging the units after placing them in the console...

Is there anything I'm doing wrong? Is there anything I can do to fix it?

 

[ds34]

This doesn't sound like a broken SD card reader etc. but like your board has some other faults if you also get those text corruptions on memloader.

 

[AlexMCS]

This doesn't sound like a broken SD card reader etc. but like your board has some other faults if you also get those text corruptions on memloader.

Nope, the text corruption only happened once.
After that, the SD isn't recognized anymore, using either reader (the new one, or the replacement i bought).

 

[SlegBE]

Can you check if all connector pins are strongly soldered.

I repaired 2 switch with 1 or 2 pins that were not soldered to the connector anymore...

 

[AlexMCS]

Can you check if all connector pins are strongly soldered.

I repaired 2 switch with 1 or 2 pins that were not soldered to the connector anymore...

I tested for resistance with a multimeter, seemed fine. Guess it's something on the MB after all.
I'll send it to a repair shop around here tomorrow since I don't have any better tools to test with.

Thanks for your help guys.

 

[AlexMCS]

So, since I got a new unit, I tried to look further into this, because every repair shop around here refused to service me due to being overwhelmed with other switch units already... Go figure.

While in Hekate (without Nyx, since the SD is not detected), selecting Tools... SD info... without a SD card inserted, gives the warning that no SD card is inserted (as expected).

If I do insert a SD card in there, it warns me that the SD reader must be reseated. I tried with 3 different SD readers, same message.

Booting into Horizon OS, surprisingly, makes the SD get recognized. I copied the only game I got in there (Disgaea 5) to the SD card to test, and voilá! It works.

WTH is going on!? -__-

Edit: I updated the system to 10.2.0 and tried again.

Booting with hekate_ctcaer_5.3.3.bin, brings up the Hekate-IPL splash screen, then shuts down the system.
Booting with the latest fusee-primary.bin (Atm 0.14.4) directly seemingly works, but Atmosphere crashes when loading the "Album".
Rebooting into Hekate brings me to that weird corrupted version of Nyx.

 

[AlexMCS]

Anyone got a clue?

Hekate is still giving me that weird screen, when it does detect the MicroSD: