Switch seems stuck in RCM

[Milenko]

Put your sd back in and hold minus to bypass the autoboot so you can get into hekate, and check what the battery percentage is

 

[Nabby]

If it were me, I would grab another SD card I have lying around. It doesn't have to be a big one. Anyone who has had phones for a while will probably have 2/4/8gb cards around that they outgrew. If not, cards that size are pretty cheap. I just saw a 32gb SanDisk on Amz for $7.
Anyway, format the new SD card in FAT32, make sure it's in MBR not GPT mode (Switch may not care about this, I just always do it regardless because the 3DS sure does). Go to the github and get the most recent Hekate. Stick the bootloader stuff on the SD card and put it in the Switch. Boot the switch in RCM and use Tegra to send the new Hekate payload. See if you can get the Hekate graphical menu.
If it still goes to text only mode, you can probably assume that the SD card slot is having problems. If you do get the Hekate graphical menu, you can work on other fixes from there.

 

[V-T]

It possibly doesn't display the option to restore the nand backup because it doesn't detect the SD card. I know you said it doesn't boot Hekate with the SD card in, but have you tried inserting the SD card after you booted the text version of Hekate? Besides, how would you restore the nand if the SD card is not in? (I'm probably not making much sense, am I?)

Don't worry, you're making perfect sense! Hekate does load with the SD card in but only if I don't have Nyx. If I run Hekate without the SD card and insert it afterwards it's the same as if I ran it with it already in - unless Nyx is on the SD card, then I only get the splash screen, then the screen goes black. Under Console Info I can view the SD card info perfectly fine, though I'm not sure how much that's worth.

Put your sd back in and hold minus to bypass the autoboot so you can get into hekate, and check what the battery percentage is

It's showing 102.2%, the charge varies though right now it's 0mA.

If it were me, I would grab another SD card I have lying around. It doesn't have to be a big one. Anyone who has had phones for a while will probably have 2/4/8gb cards around that they outgrew. If not, cards that size are pretty cheap. I just saw a 32gb SanDisk on Amz for $7.
Anyway, format the new SD card in FAT32, make sure it's in MBR not GPT mode (Switch may not care about this, I just always do it regardless because the 3DS sure does). Go to the github and get the most recent Hekate. Stick the bootloader stuff on the SD card and put it in the Switch. Boot the switch in RCM and use Tegra to send the new Hekate payload. See if you can get the Hekate graphical menu.
If it still goes to text only mode, you can probably assume that the SD card slot is having problems. If you do get the Hekate graphical menu, you can work on other fixes from there.

Hm, the only extra SD card I have is the one in my phone and I already tried it. If Nyx is on there, I can only get to the splash screen, text mode works fine except, as it turns out, some options are missing; the same behaviour as with my Switch SD card. I could get a new SD card if it could possibly make a difference though.

While I was at it, I checked the eMMC info under Console info, the GPP partition table comes up blank. Gave it a few minutes to load in case it needed time but still nothing. I don't presume that's normal.

So I guess the two possible problematic components are either the SD card reader or the eMMC, then?

 

[Nabby]

They way I'm looking at it, the first step is to at least try to rule out hardware problems, and the only hardware you can change right now is the SD card. When you boot Hekate and Nyx you haven't touched any MMC yet. If the eMMC was bad, you'd still be able to boot into Nyx to be able to load an EmuMMC if you had it. So why can't you get into Nyx is the question. Granted there could still be other hardware failures in the switch that are causing problems - I suppose the text mode Hekate payload may be small enough to slip in without triggering a failure with the system's CPU or RAM or other internal components if those were damaged. Or being in text-only mode may not be making the GPU chip process any graphical instructions if the GPU were failing. So I really feel like getting Nyx to run is a baseline, and once that hurdle is passed, you can go from there getting a working FW either on eMMC or SD.

The reason I'm hesitant to use an SD card that's been in an Android phone is that some of my SD Cards that I stuck in an Android phone were "prepared" for use by the device, and they added a tiny 16mb-ish partition at the beginning of the device and a second larger partition for main use. I don't know how the Switch would react if there's more than one partition on that SD card. I guess you can try sticking the SD card in a card reader and in Windows go to "create and format hard disk partitions" and see how many partitions show up for that drive.

 

[The Real Jdbye]

They way I'm looking at it, the first step is to at least try to rule out hardware problems, and the only hardware you can change right now is the SD card. When you boot Hekate and Nyx you haven't touched any MMC yet. If the eMMC was bad, you'd still be able to boot into Nyx to be able to load an EmuMMC if you had it. So why can't you get into Nyx is the question. Granted there could still be other hardware failures in the switch that are causing problems - I suppose the text mode Hekate payload may be small enough to slip in without triggering a failure with the system's CPU or RAM or other internal components if those were damaged. Or being in text-only mode may not be making the GPU chip process any graphical instructions if the GPU were failing. So I really feel like getting Nyx to run is a baseline, and once that hurdle is passed, you can go from there getting a working FW either on eMMC or SD.

The reason I'm hesitant to use an SD card that's been in an Android phone is that some of my SD Cards that I stuck in an Android phone were "prepared" for use by the device, and they added a tiny 16mb-ish partition at the beginning of the device and a second larger partition for main use. I don't know how the Switch would react if there's more than one partition on that SD card. I guess you can try sticking the SD card in a card reader and in Windows go to "create and format hard disk partitions" and see how many partitions show up for that drive.

I seem to remember reading that Hekate doesn't work properly with a faulty eMMC so that could be it.

 

[Nabby]

I seem to remember reading that Hekate doesn't work properly with a faulty eMMC so that could be it.

I suppose one option would be to use Tegra Explorer to see what file structures the system can and can't see. It might give some clues to if the eMMC is damaged, or if it can't read the SD Card.

https://github.com/suchmememanyskill/TegraExplorer

 

[V-T]

They way I'm looking at it, the first step is to at least try to rule out hardware problems, and the only hardware you can change right now is the SD card. When you boot Hekate and Nyx you haven't touched any MMC yet. If the eMMC was bad, you'd still be able to boot into Nyx to be able to load an EmuMMC if you had it. So why can't you get into Nyx is the question. Granted there could still be other hardware failures in the switch that are causing problems - I suppose the text mode Hekate payload may be small enough to slip in without triggering a failure with the system's CPU or RAM or other internal components if those were damaged. Or being in text-only mode may not be making the GPU chip process any graphical instructions if the GPU were failing. So I really feel like getting Nyx to run is a baseline, and once that hurdle is passed, you can go from there getting a working FW either on eMMC or SD.

The reason I'm hesitant to use an SD card that's been in an Android phone is that some of my SD Cards that I stuck in an Android phone were "prepared" for use by the device, and they added a tiny 16mb-ish partition at the beginning of the device and a second larger partition for main use. I don't know how the Switch would react if there's more than one partition on that SD card. I guess you can try sticking the SD card in a card reader and in Windows go to "create and format hard disk partitions" and see how many partitions show up for that drive.

Ah, no, I backed everything up from that phone SD card, re-formatted it and only then put Hekate on it. No difference in behaviour from my Switch SD card, I don't think being in an Android phone before hand had a chance to affect it really.

I suppose one option would be to use Tegra Explorer to see what file structures the system can and can't see. It might give some clues to if the eMMC is damaged, or if it can't read the SD Card.

https://github.com/suchmememanyskill/TegraExplorer

Didn't know this tool existed, neat! Although it injected successfully, something flashed on the screen for a split second and then nothing happened. The screen is black, the device immediately turned off, the way it does with Atmosphere and Nyx.

I seem to remember reading that Hekate doesn't work properly with a faulty eMMC so that could be it.

Honestly, considering the weird behaviour with Tegra Explorer and the fact that Hekate can't read the GPP partition at all, I wouldn't be too surprised.

 

[Nabby]

Well, if we're starting to get really desperate, it's possible to mount the switch's eMMC as a drive on your PC through USB. You'll have to use the BISKEYDUMP payload to dump your BIS keys. It has an option to save the keys, but it doesn't actually save the ones you need. Either copy what's on screen or scan the QR code it generates. Then you can use the MEMLOADER payload, while running HacDiskMount on your PC with the BIS Keys it asks for to mount your eMMC to a drive letter. Just be careful not to fiddle with anything too much. You've got a lot of power in your hands here.

https://switchtools.sshnuke.net/

 

[The Real Jdbye]

Well, if we're starting to get really desperate, it's possible to mount the switch's eMMC as a drive on your PC through USB. You'll have to use the BISKEYDUMP payload to dump your BIS keys. It has an option to save the keys, but it doesn't actually save the ones you need. Either copy what's on screen or scan the QR code it generates. Then you can use the MEMLOADER payload, while running HacDiskMount on your PC with the BIS Keys it asks for to mount your eMMC to a drive letter. Just be careful not to fiddle with anything too much. You've got a lot of power in your hands here.

https://switchtools.sshnuke.net/

Yeah, he could restore a NAND backup that way, assuming the chip isn't faulty. If the chip is faulty, it can be replaced, but flashing a NAND backup onto a blank chip isn't straightforward, and needs some extra steps.

 

[V-T]

Well, if we're starting to get really desperate, it's possible to mount the switch's eMMC as a drive on your PC through USB. You'll have to use the BISKEYDUMP payload to dump your BIS keys. It has an option to save the keys, but it doesn't actually save the ones you need. Either copy what's on screen or scan the QR code it generates. Then you can use the MEMLOADER payload, while running HacDiskMount on your PC with the BIS Keys it asks for to mount your eMMC to a drive letter. Just be careful not to fiddle with anything too much. You've got a lot of power in your hands here.

https://switchtools.sshnuke.net/

Got my BIS keys. Memloader lets me mount my SD card no problem, but not my eMMC - it just crashes when doing that, the same way Tetra Explorer and Nyx do.

Yeah, he could restore a NAND backup that way, assuming the chip isn't faulty. If the chip is faulty, it can be replaced, but flashing a NAND backup onto a blank chip isn't straightforward, and needs some extra steps.

I'm guessing that after all these attempts, I can safely assume my chip is faulty? I can order a new one, though it'll take a while to ship (since I can't find a shop selling these in my country, Aliexpress seems like the only option lol). What are those extra steps? Could you point me to a guide on the subject? (not entirely sure how to Google it)

In a way, I hope it's the eMMC chip, way better than damaged RAM or CPU. Plus, I have rock solid backups, so it's not the end of the world.

EDIT: Okay, so I actually got it running. This is surreal.

I opened it up to check how the eMMC chip looks. I noticed the batery wasn't plugged in - I assume the repair shop people forgot to plug it in. After I plugged it in and pressed the power button, stock firmware turned on. I flashed Hekate (no problems with Nyx this time), I was able to launch Atmosphere no problem. Everything's fine. I can't believe they missed this, I have no idea how this could have happened in the first place.

Either way, thank you all for helping, I'm beyond happy I got it running, without having to deal with replacing the chip and all.

 

[The Real Jdbye]

Got my BIS keys. Memloader lets me mount my SD card no problem, but not my eMMC - it just crashes when doing that, the same way Tetra Explorer and Nyx do.


I'm guessing that after all these attempts, I can safely assume my chip is faulty? I can order a new one, though it'll take a while to ship (since I can't find a shop selling these in my country, Aliexpress seems like the only option lol). What are those extra steps? Could you point me to a guide on the subject? (not entirely sure how to Google it)

In a way, I hope it's the eMMC chip, way better than damaged RAM or CPU. Plus, I have rock solid backups, so it's not the end of the world.

RAM and CPU are unlikely to fail randomly, and if they were, it's likely the console wouldn't show any signs of life.
It might just be corrupted and not faulty, corruption is often an indication of a faulty chip but could also be caused by a system crash during writing, so I wouldn't entirely rule out it being salvageable, you should at least try to restore a NAND backup before you write it off as faulty.
You could take the opportunity to upgrade the eMMC to a larger size, there are replacement modules (plug & play) available in larger sizes like 128 GB and I think even 256 GB.
I'm not sure what guide to use, every guide I see assumes you don't have a NAND backup and uses a NAND backup from a donor Switch instead, but it looks like they just flash the NAND backup directly to the blank eMMC with Hekate so maybe I was wrong that there are extra steps needed? I guess you should try it, and report back if it gives an error.

 

[Nabby]

Congrats on getting it working! I'm sure that's a huge relief, and I'm guessing you learned some things and added some useful tools to your arsenal. Happy gaming!

 

[Milenko]

How did your battery say 102% charged if it wasn't plugged in?

 

[V-T]

How did your battery say 102% charged if it wasn't plugged in?

No clue. When I did plug it in, it was at 23%, so I assume Hekate just got confused? It was a weird thing it was displaying but I didn't pay it any mind; it would've never crossed my mind to check the battery. Especially since I never would have guessed the repair shop people didn't plug it in.

Congrats on getting it working! I'm sure that's a huge relief, and I'm guessing you learned some things and added some useful tools to your arsenal. Happy gaming!

Thank you! I honestly have a nice folder filled with really useful tools for the future, I feel like I actually learned a lot about Switch troubleshooting in the process, so even though the issue was somewhere else entirely, I don't think it was wasted time. In case something happens in the future, I won't immediately freak out and that's good.

Once again, a big thank you to everyone who helped me. I don't think I've been this happy to play Mario Kart in a long while.