Any payloads are fine but unable to boot on HOS neither Android

Hello there,

I bought a used Switch in order to try to fix it. The seller told me that this switch failed to a software upgrade.

Here is the situation :

No autoRCM
15 fuses burnt
USB-C port is fine to communicate with the SOC through D+ and D-
Battery voltage at 4V
eMMC readable and writable, benchmack via Hekate is good
LCD and touch Panel are fine via Hekate
SD card reader is fine to read and write my EVO SD card from Samsung
Fw is 10.1.0 with Tegraexplorer

There is absolutly no problem to use this switch with these payloads :

Hekate is able to read and write my SD card, backup and restore my eMMC
Tegraexplorer, Lockpick and biskeydump are able to backup keys

At the beginning i thought that it was just a mismatch between 15 burnt fuses and a 10.1.0 firmware so i follow a guide from suchmememanyskill to upgrade then wipe to firmware 13.2.0.

Unfortunatly i’m still stuck on black screen when I power up the switch. So in order to know if it’s a software or a hardware default, i decided to install Android on my SD card.

There is no problem to install Android with Hekate but when the switch reboot for the first time to TWRP there is still a black screen.

Same issue when i use an EMUNAND with Atmosphere, i only see the splash screen of Atmosphere then again a black screen …

If i’m unable to boot on Android and genuine 13.2.0 firmware, it must be a hardware failure but i’m unable to guess which parts fail inside this switch.

Thank you for your help.

Hey @Sephiroth

Have you tried booting Ubunto Linux on it?

I had a similar issue with my switch where it wouldn’t load anything passed Hekate but could load all the things yours can and it turned out to be one of the MAX77621 IC’s at fault preventing voltage to boot the firmware (including Linux).

There are some very clever users on this forum that should be able to advise a starting point in your diagnostics journey though as I have only fixed one so far and it took me months

Hello @Guy1980 ,

Thank you for your answer. I do not try Ubuntu Linux, it costs nothing to try it. I’m going to looking for a tuto in order to install Ubuntu Linux. I need some time maybe this week-end.

Your case about your MAX77621 IC is interesting. Do you remember having any shorts on the caps around this ic or other issues?

I made some quick tests on the caps around my MAX77621 IC and i do not find any short.

I wiil continue to dig about this IC by reading posts on this forum.

Thank you.

Hello @Guy1980 ,

Last week-end, I installed without any problem Ubuntu thanks to Hekate, but unfortunately when Ubuntu must boot, it freezes on the splash screen “switchroot UBUNTU”

So it must be a hardware failure. I have to tear down again my switch and check my MAX77621 ICs.

Good night.

Hi there, where you able to fix this problem?? I’m having the same issue!

Hello,

i actualy failed to find the root cause about this issue.

Sorry.