Hi all, I have been suggested to post my issue in this thread so here we go:
I have a mariko Switch with a Picofly chip. It worked just fine until one day after many hours of use the application freezed, in Atmosphere. After reseting it, it booted normally, but it freezed again after a shorter period. After that it inmediately freezed while trying to turn it on again, sometimes not even booting and giving the error 2162-0002, amongst others.
I let it stay for the night and the next day it worked fine for many hours until the same happened again. After that the frequency of the crashes increased again.
First I though it could be corruption in the emuMMC or an SD fault, but the freeze also happened booting Stock firmware. I've tried different SD cards, factory reseted SysNAND and reinstalled everything but no luck. I've made it freeze in Atmosphere, Stock and Hekate. Even removing the modchip and booting OFW with no SD card.
The time it takes to freeze the first time from a cold boot is random, but it is usually long. Sometimes I get to play for an hour. After that it is much faster, a few minutes usually. This is consistent.
This has led me to think it is a temperature related issue instead of a problem with the eMMC. I have alsoreplaced the MT92 IC in case it was faulty, but the problem persists.
When the console freezes while in Hekate, CPU temperature readings are slightly above 30Cº (no heatsink). Current is in between 200-300 mA depending on backlight strength, so it seems normal. I checked for shorts in all supply rails but everything seems fine, just measuring some low impedance in the CPU supplies but it should be normal.
Finally, I looked at the board with a thermal camera after booting Hekate and I see a hotspot right above the MT92 IC. It inmediately reaches 42Cº with no activity. While in a game it gets hotter, I've measured up to 60Cº after a few minutes into a game.
This IC that's getting hot has the markings PP5 951. As I understand this is a MOSFET. Is it normal it gets this hot?
I don’t have pictures at hand ATM, but I can take some if needed.
P.d.: Also, in very rare ocassions the application crashed but I could get back to the home menu. Then it would crash shortly afterwards but this is definitely a different behavior. eMMC corruption? If the eMMC is broken why does temperature have an effect on the crash frequency?