Black screen - Fuse mismatch?


I have a switch that won’t boot into anything (OFW, CFW)
OFW will just remain black when either booting normally or selecting OFW in hekate
CFW will get to the atmosphere logo and freeze at said logo

It is unpatched and I am able to get into hekate and will include an image of the fuse info

The switch had no p13usb originally and required a port replacement (a pin was pushed back into the port grounding it)

No shorts were found anywhere on initial inspection before any IC replacements

What I tried:
Put a new p13usb (was missing)
Replaced M92t36 in case of damage from the previous usb port
Replaced Bq24193
Replaced the fuel guage IC
Two different firmware nand rebuild methods (had no issues dumping anything)

Additional information:

Diode readings always taken with red probe on ground

Rail → black on ground → red on grnd → Diode

0v8 CPU → 216 Ω → 285 Ω → 0.215v
0v8 GPU → 74 Ω → 88 Ω → 0.124v
1v1 → 1.01k Ω → 303 Ω → 0.171v
1v8 → 5.06k Ω → 3.83k Ω → 0.39v
1v8 alt → 0.86m Ω → 0.74m Ω → 0.56v
1v15 → 55 Ω → 63 Ω → 0.096v
1v35 → 60k / 3.6m Ω → 34k Ω → 0.47v
3v3 → ~5k / 2.6m Ω → 5.84k Ω → 0.44v
5v → 3.35k Ω → 3.2k Ω → 0.53v
sys → 270k+ Ω → 4.2k Ω → 0.37v

If anyone has an idea or something obvious that I missed, please let me know!


I should mention I get all voltage rails other than 0v8 GPU, don’t think the switch boots far enough to enable that line, anyone know a way to test if the 0v8 GPU rail enables?


Went ahead and replaced the 0v8 gpu buck converter since I am unable to the voltage on that line, it made no difference unfortunately…

Forgot to mention it draws 0.46a from a 5v (pc connection)
I did get an official nintendo charger today and when using it the draw is 0.47a / 0.48a

with nothing connected the board draws;
0.22a (5v pc connection)
0.08a (15v nintendo charger)

Could this nintendo charger be faulty? it isn’t a new one

Also, can someone confirm if the soc/cpu should get warm when the motherboard is drawing current?


So I had some time to mess with this switch some more, noticed I was missing one of the small voltage rails coming from the max77620A, I went ahead and replaced the IC and ended up with a 0.0a draw

Reflowed the max77620A after finding an OL on one of the caps near the IC, after the reflow I had the correct reading on said cap

After plugging in the charger, the amp draw shot straight up to 0.48 with nothing else connected and produced a warm SoC, Figured I nudged it too hard so I removed the max77620A again

Reballed by hand the original max77620A in case the one I got from ali was faulty (it did have marks on it as if it was a used ic when I received it)

With the newly reballed max77620A(original) I receive all expected voltage rails but I am back to the 15v 0.0a draw with no response when attempting to power on, I suspect the ‘replacement’ max77620A was fine when I first put it on as I had the same 15v 0.0a

Anyone have any ideas on what could cause a 0.0a draw?