Nintendo Switch HAC-CPU-20 require some repair help please

Nintendo Questions Nintendo Switch
113

@Severence @zyrex
Is this what you meant??? (see below)

No RCM device detected
RCM Device detected
RCM device disconnected
RCM Device detected
Preset “PAYLOAD_FILE” set to : C:\Program Files (x86)\TegraRcmGUI\favorites\hekate_ctcaer_5.0.0.bin
Invoking TegraRcmSmash.exe with args : “C:\Program Files (x86)\TegraRcmGUI\favorites\hekate_ctcaer_5.0.0.bin”
TegraRcmSmash (32bit) 1.2.1-3 by rajkosto
Opened USB device path \?\usb#vid_0955&pid_7321#7&1f3d457c&0&3#{aa0dbd45-3117-f331-5c49-76bf65225042}
RCM Device with id 0002FF060000001440D6416401101062 initialized successfully!
Uploading payload (mezzo size: 92, user size: 126207, total size: 192423, total padded size: 192512)…
Smashing the stack!
Smashed the stack with a 0x001f byte SETUP request!
Payload successfully injected
RCM device disconnected
RCM Device detected

114

See this video here, at 7:17

After injecting a payload, in the log output following “smashing the stack” you’ll get a hex code

It would seem though the the code spat out in your case - “0x001f byte SETUP request!” is a bit different to what I’ve seen before… bear with me

115

do I need to assemble the whole switch before I can get this information? or can I just get do this with the barebones board and no eMMC attached

116

No, all you need is the board with the battery connected and USB connected. leave the EMMC disconnected so it remains in an RCM state

I’ve searched online and some are putting this code down to either a bug with TegraRCMGUI or an issue with the newer version of Hekate :man_shrugging: not had this issue before myself

Maybe try using the previous version of TegraRCMGui (with the APX driver installed if it isn’t already) and using an older version of the Hekate payload, or just use the Biskeydump payload instead and see if that works :slight_smile:

117

@Techie_hobby1 Try downloading newest hekate, it’s 5.8, you still using old 5.0

https://github.com/CTCaer/hekate/releases/download/v5.8.0/hekate_ctcaer_5.8.0_Nyx_1.3.0.zip

118

I tried still with the new version of Tegra and updated to new version Hekate and got this now

Smashed the stack with a 0x7000 byte SETUP request!
Payload successfully injected

119

Also have received delivery of P13, USB, BQ and Fuel Gauge ready to swap out one by one

120

perfect, the switch is unpatched :+1:

So now try with everything hooked up (exl the EMMC) , put the files for Hekate on the SD and inject the Hekate payload, see if you get anything on the display and if you do take some photos of the console info section - with the fuel gauge stats etc

1 Like
121

@Severence
Okay brilliant so we are getting somewhere now very slowly but hopefully surely.
I am out for most of the rest of the day now but if I get back earlier I will give the next steps a try…otherwise I will return to my bench tomorrow and commence then.

Also, SD card …
What type/size etc…do I need any particular size?

Lastly, out of interest though… what information will this payload give me??

122

Any size, Fat32

Hekate will first confirm display/backlight is working (if you get a display), allow you check fuel gauge stats (which will for the most part verify if it’s good/bad in most cases) will allow you to verify the EMMC if it can be read (will cover later)

1 Like
123

@Severence @zyrex
I am having a bit of a mare here today.

I followed all the steps today…
I’ve installed the following:
Spare battery (one with known charge),
Power button,
LCD connector,
Backlight cable,

  • SD card reader

Plugged USB in (connected to PC) now it’s constantly saying “unable to recognise USB”

So all in all I cannot get the Switch into Rcm Mode no matter how hard I try……

What am I doing wrong?

124

verify the USB port is clean and there are no bent pins - after that i would suspect M92 issue… but just to make sure something else isn’t a miss… once again disconnect everything but the battery and see if the symptoms change, who knows, if it does, might be pointing to the culprit.

125

@Severence @zyrex
Just seems very odd…
I have checked the USB connector and checked the pins; all seems clear to me.

When I did the Rcm mode the M92 was/is already reinstalled and it worked then… nothing else has changed other than the LCD, backlight and button being connected.

I am wondering if the LCD connector is still not playing ball and causing the board to play silly sods with me.
I’ve checked all the Caps and I do not have any shorts what so ever.
Also earlier…I installed the battery (spare one with charge) and power button.
Pressed the power button and tested M92 at Pin 5 (input) = 3.283v
Pin 6 (Output) = 3.297v

I didn’t get round to removing the connections today…
I will do this tomorrow and will update you with the results.

126

@Severence @zyrex
Stripped this Switch back down to barebones…

Ran TegraRcmGui
Plugged in (Spare battery with charge) and USB

Guess what… RCM mode found :face_exhaling:

I will plug in bit by bit connections and see which one is causing RCM mode not to load… my guess is LCD Connector

127

@Severence @zyrex
Yep…
Went through the connections one by one connecting up to RCM mode… all was good until LCD connector was attached then it all went bad and no RCM mode connection.

I am going to carefully again attempt to reflow this connector… or am I better just lifting it off, wicking up the solder and starting again.

Note: I cannot see anything wrong with the connector and as this is my last one I will have to (unless it is damaged) make do with returning this one back in place

128

Before removing it, take a very careful look with the latch up inside and see if any of the pins are bent, as often times they bend and then when the ribbon is inserted these bent pins touch something they shouldn’t. - don’t recall if you said if you have a microscope, but if you don’t use your phone camera and zoom in to get a better look

Failing that I would probably go ahead and swap the connector out in it’s entirety as I would imagine something has bridged as a result of the manual soldering you did earlier. So I’d just whip it off, start again with a fresh connector and reprepped pads. If you must use the existing connector again, after you’ve removed it, make sure it’s not too melty and looks decent

btw I mentioned based on your earlier pics how your joints looked cold, if the solder your using is chinese so called “63/37” or so called “60/40” just dump this stuff and instead get a decent roll of chip quik 63/37 on Mouser, you’ll find it is much higher quality and actually melts at genuine leaded temps, which will make rework such as this easier for you and look nicer :slight_smile:

129

Also make sure it’s Clean.
Sometimes there is flux in it, need some good cleaning.
Best heat it up a bit (like 170c) and then Clean it with IPA.

130

@Severence @zyrex

I thoroughly checked that connector and it has no issues…
No bridges
No damage etc…

I have Rcm Mode - OK (Green) but can’t work out how I get SD card to read Hekate

Steps I have taken >

I removed, wicked up old solder, applied new solder…
Reinstalled connector -
checked every pad against corresponding pin…

Connector is good…

Plugged everything in (Battery -Spare , LCD , Backlight, Power button)

Plugged into USB ran TegraRcmGui

Downloaded Hekate to SD card

BUT can’t work out how to run from SD card??

131

@Severence

I know you said it would be better to install a new connector - but I do not have anymore spares and I am running out of time for getting this Switch working before my friends son is going to be getting very upset… So have to make do with this one for now…

If I have to re-order one then I will do so but this connector is being recognised now but LCD is not

132

Make sure you’ve put all the Hekate files as per it’s instruction in the correct destination… alternatively you can use a much older version of Hekate which will boot in text only mode which does not require files on the SD (just as an intial test)

And alternatively again, you can just use the Biskeydump payload (again, just as a test)

If either of those two payloads (without the requirement of SD files) work above (and you get a display) and after if your still having problems with the files on your SD, then hop over here

And scroll down to the " Step 3: Setting up your SD card" section and try using those instructions/files instead