Hacking Hardware Blue screen of death installing and removing Hwfly Switch v2

[minimanimo]

You can check which stage the console is stuck at by probing emmc data pins if you have an oscilloscope/logic analyzer, or by measuring current draw. Here's a detailed guide:
https://www.retrosix.wiki/emmc-booting

Pretty sure the problem is the emmc chip. You can buy replacement ones on aliexpress for about $10

Unfortunately, I don't have such strumentation.

I have tried desoldering everything, cleaning the CPU of any residue and booting but it makes no difference. The impedances, in continuity mode of the multimeter, look good on the CPU (I tested condensators in the row where I soldered).

I then tried installing the chip from scratch but unfortunately I still get *==.
So anyway, I have to think that the power supply is there somehow, because the chip is supplying power.
It scares me that the signal ("poor wiring, or dead CPU") is in the second case.

Pretty sure the problem is the emmc chip. You can buy replacement ones on aliexpress for about $10. You also need mmcblknx, regular emmc to sd card adapters won't work, it has to be a realtek chipset one iirc so it can write to boot partitions. Or you can use emmc programmer if you got one.


You can generate boot0/1 partitions with EmmcHaccGen, and I believe that's the minimum requirement to boot a switch to hekate with modchip. Then you can follow through the emmc rebuild guide and see if you can recover your original emmc partitions, otherwise you won't be able to play online anymore.

So if I get a new clean emmc and plug it in, if the CPU is still technically alive, I should be able to go back to the "No sd card" screen, right?
And then I would be able to rebuild the emmc in any case but I cannot go online unless I recover the keys from my (possibly) dead emmc.

If yes, for such work I can get any emmc on Aliexpress or should I take a specific one (exactly as mine?)

Post automatically merged: Jul 19, 2023

What I don't understand is the way it got corrupted: it worked until I've closed the black cover. Rechecking, I don't think a short could be between emmc and modchip by touching each other. I am more thinking if maybe the soldering on capacitors did touch the metal cover somehow.

 

[randy_w]

Yes, you can get any emmc module, but I'd say just get a samsung one. You can also upgrade the internal emmc to 64GB or 128GB if you want, here's your chance.
Iirc you still need to program the new emmc's boot0/1 with your own prod.keys, but I'm not 100% sure if that's the case with modchips, actually I've never done emmc transfer/rebuild with modchip, so you might as well start a new thread and ask for suggestions from others who've done this before.

 

[minimanimo]

Yes, you can get any emmc module, but I'd say just get a samsung one. You can also upgrade the internal emmc to 64GB or 128GB if you want, here's your chance.
Iirc you still need to program the new emmc's boot0/1 with your own prod.keys, but I'm not 100% sure if that's the case with modchips, actually I've never done emmc transfer/rebuild with modchip, so you might as well start a new thread and ask for suggestions from others who've done this before.

Thank you so much for what you have done so far @randy_w

I was thinking: what if I can get an already programmed emmc of another nintendo switch? Possibly, could the console work just by plugging it in?
I suppose yes, being memory, but asking for confirmation as I have no idea if there is any constraint/coupling to other hardware for protection.

 

[randy_w]

I was thinking: what if I can get an already programmed emmc of another nintendo switch? Possibly, could the console work just by plugging it in?

Normally this isn't possible, but I'm not sure if things change with modchip.

 

[arvs]

I think It is clear that OP is not adding a tape between modchip and EMMC module. I installed Picofly myself but I found it bad to not put an insulation between modchip and EMMC sandwich. IT WILL SHORT SOME COMPONENTS WHEN PRESSED AGAINST. Your EMMC and possibly modchip will be fried when bad power goes into something it should not. Always think of those situations.

And also OP, please cut yourmain metal shield to allow space for the mod chip. Draw a line using a sharp object and literally cut it with a metal scissor, easy.

I also added an insulating foam tape (which also has double sided adhesive between the passive components beside the emmc between emmc chip and the ram shield. Emmc is fine touching the RAM shield for added cooling.

p.s. We use Capacitors now instead of word condenser. How young are you?
p.p.s. I did not update the modchip after bying it off from aliexpress.

 

[minimanimo]

Hi @randy_w ,
I have news! I've collected the mmcblkNX and I was able to read the emmc partitions!
Indeed, I have just backed up the boot0, boot1 and whole raw nand.

I would then assume I have a working Emmc. I have also tried to write another firmware on the HwFly RP2040 and it worked, but I don't know if this is sufficient to say the modchip still work as expected.
It might be, for some reason, the boot partition are messed up.

Hi @arvs, thanks for stepping into this topic. If you check my previous messages, the metal plate has been indeed cut to host the modchip. But yes, I was naive and I didn't put kapton between emmc and modchip.

-----
Any suggestion in how to rebuild/retrieve those, at least to try to boot the switch with original firmware and without modchip?

Thanks!

 

[randy_w]

Hi @randy_w ,
I have news! I've collected the mmcblkNX and I was able to read the emmc partitions!
Indeed, I have just backed up the boot0, boot1 and whole raw nand.

I would then assume I have a working Emmc. I have also tried to write another firmware on the HwFly RP2040 and it worked, but I don't know if this is sufficient to say the modchip still work as expected.
It might be, for some reason, the boot partition are messed up.

Hi @arvs, thanks for stepping into this topic. If you check my previous messages, the metal plate has been indeed cut to host the modchip. But yes, I was naive and I didn't put kapton between emmc and modchip.

-----
Any suggestion in how to rebuild/retrieve those, at least to try to boot the switch with original firmware and without modchip?

Thanks!

You can then try to generate boot0/1 partitions with emmchaccgen, I think you can try to use another console's prod.keys if you didn't make your own, since you are using a modchip. Then write generated boot0/1 to emmc and see if switch boots up.
If everything goes well, you should be able to boot to hekate, then you can dump your own keys with lockpick_rcm. Once you have your own keys, you can assess the damage in nxnandmanager. Since your switch blue screened without modchip, I'm pretty sure the partition table's gone. You can then follow through the guide to rebuild emmc with a donor nand.

Post automatically merged: Aug 4, 2023

Actually I think sthetix made a detailed guide for nand rebuild, let me try to find the video for you

Here you go:

 

[minimanimo]

You can then try to generate boot0/1 partitions with emmchaccgen, I think you can try to use another console's prod.keys if you didn't make your own, since you are using a modchip. Then write generated boot0/1 to emmc and see if switch boots up.

Oh, might sound a possible way to go.
Would it work by using prod keys from another switch with different model and firmware? I might have the possibility to get keys from an "Erista" of another user

Post automatically merged: Aug 5, 2023

You can then try to generate boot0/1 partitions with emmchaccgen, I think you can try to use another console's prod.keys if you didn't make your own, since you are using a modchip. Then write generated boot0/1 to emmc and see if switch boots up.
If everything goes well, you should be able to boot to hekate, then you can dump your own keys with lockpick_rcm. Once you have your own keys, you can assess the damage in nxnandmanager. Since your switch blue screened without modchip, I'm pretty sure the partition table's gone. You can then follow through the guide to rebuild emmc with a donor nand.

Post automatically merged: Aug 4, 2023

Actually I think sthetix made a detailed guide for nand rebuild, let me try to find the video for you

Here you go:

It's weird because, comparing with the one of the youtube video, the partitions on my nand still look good

 

[minimanimo]

Hey @randy_w ,

I've finally managed to go back to the initial status where the modchip was working and it boots to the "No SD Card" screen with an HwFly RP2040 (picofly clone). After several checks of the motherboard electronic, I've changed the V2 flat and finally got back to work.

Now it consistently boots, but if insert a microsd with Hekate + Atmosphere package, after the glitch (so blue led and then yellow led) I get a black screen.
If I remove the micro sd card from the reader and power on, the “No SD Card” screen is shown successfully.

I tried with 3 different SD cards (256GB, 64GB and 32GB). I have tried formatting with both “SD Card formatter” and “Rufus”.
For the content: I tried an already complete package found in a tutorial, I also tried another package from [KEFIR 709, Atmosphere 1.5.5, hekate 6.0.6].
Nothing, still the same problem.

Any idea/tip? Thanks

 

[randy_w]

Since you already tried several sd cards i think we can rule out sd card/format issue. But just double check you are formatting it into MBR/FAT32, you can try another tool fat32 format gui:
http://ridgecrop.co.uk/index.htm?guiformat.htm

I think i've seen a post here before, modchip would glitch just fine and show no sd screen but won't load payload from sd card. Maybe you can try to reflash picofly firmware, see if that helps.

Finally, some modchip designs are faulty to begin with, like some quick soldering ribbon bundled with some hwfly v5 revisions, which would cause interference and prevent the console from booting. If you ruled everything out then you might want to install another chip.

 

[Marax]

I have exactly the same problem on my switch lite with Samsung MMC… With Modchip desoldered I get an bluescreen and with modchip installed and no sd card I get the no sd card screen. With SD Card inserted I get a Blackscreen with backlight.. I don’t know what I could try