Failed to init emmc


I have a switch that has a dead emmc module and was wondering what options I have?
The switch is unpatched and I am unable to dump any backups from the nand in hekate
I can dump the prod.keys etc

I have tried to reball the nand module with no success

Temporarily using a nand from another switch shows this switch would boot
(0.0a → 0.08a → 0.0a) whereas with the dead nand the switch sits at 0.08a


hekate has feature to test emmc. If it says emmc init failed, meaning your last hope is try using MMCBLK-NX to dump all partition

Thanks for the reply, unfortunately there doesn’t seem to be any MMCBLK-NX devices in stock, guess I will look for something similar to attempt to dump the nand


I make no claims to the quality of this.

Ty sir,
I didn’t find this one when I searched ali, the V3 looks like the one i may get

did you ever end up ordering this? I am finding myself in a place where I also need one of these tools.

If Hekate cannot read data off the EMMC then MMCBLK won’t be able to either as they are fundamentally using the same lines and MMCBLK does nothing special… apart from VCCQ being 3V3 rather than 1V8 (which might actually cause issues if your EMMC is bad or failing)

If a reball doesn’t resolve the EMMC issues then you can as an absolute last resort attempt heating the IC at about 100C while attempting to recover the data - the odds are very low though and you usually have one chance and very limited time window so should prioritise getting the most important partitions such as prodinfo etc

In an ideal world we’d know which TPs (on some brands theyr’e below the soldermask on the IC) correlates to the direct NAND pads thus bypassing the likely bad EMMC controller and recovering the data in nand access mode with a microcontroller or similar. There are ways to identify these signals and in turn TP’s using an LA and there are several guides on doing this on microSD cards etc which fundamentally follow the same process you’d use on an EMMC. - Sorry I made a start on this and lost interest but if anyone wants a project there you go :slight_smile:

most common brand eMMC5.1 support dual voltages setting: 1.70V ~ 1.95V or 2.7V ~ 3.6V
reference (SEC eMMC)

Yes most do support it. some don’t.

What I’m saying is - if your EMMC is bad IE: the internal controller is dying - your far more likely to recover the data if vccq is at 1V8 as opposed to 3V3

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I did not end up getting it yet, the nand IC had a scuff mark on it and wasn’t 100% flat so one end was closer to the pcb than the other, I did reball it and had no success and figured it is physically damaged and nothing can save it

damn, I am sorry to hear that. It really sucks we get to the end of the road on repair when it comes to dead eMMC’s.

So, if we get the dreaded “Failed to init eMMC” in hekate, then even something like this is not a possible avenue?

I have been lucky in that I have not had to deal with a bad eMMC yet, but that streak was broken when my latest unpatched purchase hit my mailbox. So i’ve been reading up on how to possibly repair this, if not impossible. Just sucks we get stuck here on something that really should be a no brainer fix. Thanks, Nintendo.

I’ve not done this donor prodinfo stuff but yeah that should be possible but, well, at least in my eyes it’s unsellable afterwards as afaik you can’t use it online (at least legitimately) etc. Or the alternative you just use the Switch as an android machine :frowning:

It sucks but to be fair to Nintendo, encrypting the data / tying it the SoC is/was pretty much their only way to *attempt to combat piracy. I don’t think they were going out of their way to make repairs more difficult or’s just one of those unfortunate things. They could have been worse and paired the GC PCB etc :open_mouth:

As I say though it should be more than possible to recover the data on these bad EMMC IC’s using the “secret” NAND pads but unfortunately for whatever reason the data recovery community are very reluctant to give up this information (too much money involved in this field) as I have no doubt these nand pads have already been identified on all EMMC variants used on switch but no ones telling… but you can figure them out… just a shame it’s very time consuming :slight_smile:

yeah, in the video the creator lists that unfortunately you can not recover the original serial number from the broken NAND. So I’d imagine this is probably the reason you can’t access official nintendo servers. In that case, yeah, I’d agree. Its either unsellable or sold with a huge asterix about its condition. I think I still may attempt this because I really don’t give two hoots about making money from repairs. If I was able to revive it, the satisfaction from bringing it back from death is more than enough, plus it is in literal factory condition and I would most likely just add it to my own personal collection to play with.

Appreciate the helpful insight as always my man.

I’d enjoy trying to figure that out, I don’t have the tools required though, in my case I set that switch board aside for now and will eventually try the donor nand thing then give it to a family member, someone who doesn’t need to use it online :slight_smile:

I see. I’d just be careful with this donor prodinfo thing. I don’t know for example if you were to use one from a fully working Switch and then your patient inadvertantly connects to the internet and gets banned or whatever, I’d imagine the same thing would happen to the working one too as I don’t think Nintendo issues it’s bans based on serial numbers exclusively… though I could be wrong I’ve not looked into this :slight_smile:

I would probably use the nand from the other switch I have a post about since I was able to dumb its nand info, reminds me, I need to upload some images of that board, completely forgot.

Following as I’m interested in trying the donor prodinfo since I have a couple with bad eMMCs. You can only do this with failed to init ones? I have one that will render the switch completely dead, no rcm mode or anything.

A nand module that renders the switch dead when connected? could be a shorted cap on the nand module board

I didn’t find any shorted caps on the emmc board. It’s almost like the nand chip is shorted or something. I’m waiting on some solder balls to try a reball by hand. Attempts using a stencil have been miserable.

I also have a switch here that fails to init it’s emmc, so will likely have to start down this road when I have some spare time…