Here's a quick and easy fix for the turning off at 40% battery issue that people are seeing after running Linux. This is effectively the same fix as unplugging the battery, but does so without having to take apart the Switch.

Step 1: Download attached fusee-linux-battery-fix.rar
Step 2: Extract and load the binary with your favorite RCM Smash tool (I'm using TegraRcmSmash).
Step 3: You should see the typical fusee screen, at this point unplug the USB cable. The screen should go off.
Step 4 (optional?): Hold the power button for 10 seconds. Your switch won't turn on at this point, that's desired.
Step 5: Plug in a USB cable. Switch will turn on, and you're done.

This worked to fix my Switch, let me know if it works for you.

Edit:

Source is here:

github/crystalseedgba/BatteryFix/blob/master/fusee/src/main.c (Sorry it's not letting me post hyperlinks)

This doesn't fix the Linux bug, this is really just a crude workaround. At first I suspected that Linux is somehow mangling the battery gauge but this doesn't seem to be the case. The battery gauge reports around 40% and decent battery voltage when my Switch would turn off. I think Linux is misconfiguring some undervoltage lockout somewhere, but I don't know where.

Thanks to jjbredesen for his "How to make a custom Fusee payloads" tutorial.

 

[Shadow LAG]

Hold the phone. The way this is described, it sounds like you need to trigger bootrom > charging to bring the switch back to life if I am understanding correctly. People better be sure this isn't reliant on the bootrom as autorcm corrupts that. Autorcm can charge, but never trigger the battery / bootup sequence without first deploying a bootloader.

Has anyone confirmed bypassing this step by deploying a payload?

 

[CTCaer]

Hold the phone. The way this is described, it sounds like you need to trigger bootrom > charging to bring the switch back to life if I am understanding correctly. People better be sure this isn't reliant on the bootrom as autorcm corrupts that. Autorcm can charge, but never trigger the battery / bootup sequence.

Has anyone confirmed bypassing this step by deploying a payload?

The re-enablement of the BATFET, aka battery re-connection, is triggered only by plugging your device to USB (wall adapter or PC).
This re-enables it and you can inject a payload, or with no autorcm it will power on the console.

 

[Shadow LAG]

The re-enablement of the BATFET, aka battery re-connection, is triggered only by plugging your device to USB (wall adapter or PC).
This re-enables it and you can inject a payload, or with no autorcm it will power on the console.

Thank you for the clarification. Sounds like this is the way to go then.

 

[Sosainas]

Do you recommend to use this if I only did a nand backup with Hekate?

 

[Xellar]

Here's a quick and easy fix for the turning off at 40% battery issue that people are seeing after running Linux. This is effectively the same fix as unplugging the battery, but does so without having to take apart the Switch.

Step 1: Download attached fusee-linux-battery-fix.rar
Step 2: Extract and load the binary with your favorite RCM Smash tool (I'm using TegraRcmSmash).
Step 3: You should see the typical fusee screen, at this point unplug the USB cable. The screen should go off.
Step 4 (optional?): Hold the power button for 10 seconds. Your switch won't turn on at this point, that's desired.
Step 5: Plug in a USB cable. Switch will turn on, and you're done.

This worked to fix my Switch, let me know if it works for you.

Edit:

Source is here:

github/crystalseedgba/BatteryFix/blob/master/fusee/src/main.c (Sorry it's not letting me post hyperlinks)

This doesn't fix the Linux bug, this is really just a crude workaround. At first I suspected that Linux is somehow mangling the battery gauge but this doesn't seem to be the case. The battery gauge reports around 40% and decent battery voltage when my Switch would turn off. I think Linux is misconfiguring some undervoltage lockout somewhere, but I don't know where.

Thanks to jjbredesen for his "How to make a custom Fusee payloads" tutorial.

https://github.com/crystalseedgba/BatteryFix here for everyone thats lazy.
And thanks that worked for me.

 

[jakkal]

Do you recommend to use this if I only did a nand backup with Hekate?

It said linux
Hekate is not linjx

 

[Shadow LAG]

It said linux
Hekate is not linjx

It will fix the battery desync issue regardless of payload.

 

[jakkal]

It will fix the battery desync issue regardless of payload.

Does nand backup cause battery desyncing?

 

[Shadow LAG]

Does nand backup cause battery desyncing?

There have been a few reports in the "battery after" thread that did report battery desync with random payloads including hekate; however, the most common desync occurs from Linux.

 

[Deleted User]

i don't really know if i done it right (i needed to plug my switch in to an ac adapter from my dock to turn on)

 

[IC]

i don't really know if i done it right (i needed to plug my switch in to an ac adapter from my dock to turn on)

I had to do that too but I’m pretty sure it worked

 

[Deleted User]

I had to do that too but I’m pretty sure it worked

Yep it worked

 

[CatmanFan]

Step 1: Download attached fusee-linux-battery-fix.rar
Step 2: Extract and load the binary with your favorite RCM Smash tool (I'm using TegraRcmSmash).
Step 3: You should see the typical fusee screen, at this point unplug the USB cable. The screen should go off.
Step 4 (optional?): Hold the power button for 10 seconds. Your switch won't turn on at this point, that's desired.
Step 5: Plug in a USB cable. Switch will turn on, and you're done.

Is it absolutely required to do Step 4?

 

[Draxzelex]

Is it absolutely required to do Step 4?

Its a manual shutdown to ensure the Switch is not in RCM or some other mode before you try turning it on again. If you don't do step 4, then try to turn the console on, but it doesn't, its either already on or in RCM.

 

[CatmanFan]

It freaking worked.
Even though I didn't even use Lakka that much.
Thanks a lot, OP!

 

[Zumoly]

It freaking worked.
Even though I didn't even use Lakka that much.
Thanks a lot, OP!

How was lakka? Will you keep using it?

 

[CatmanFan]

How was lakka? Will you keep using it?

Well, it was a mess to set up. At one point, I thought my Switch was bricked but it turned out it wasn't (what a relief). Right now, I still need Paragon extFS before I can transfer my ROMs over to the Switch.
I will probably use Lakka not very often, but only when I really feel like it.

 

[GitGudScrub]

This payload is brilliant, solved the battery desync issue.
was about to disassemble the switch to disconnect then reconnect the battery
thx

 

[Deleted User]

This payload is brilliant, solved the battery desync issue.
was about to disassemble the switch to disconnect then reconnect the battery
thx

Me too

 

[Ericthegreat]

There have been a few reports in the "battery after" thread that did report battery desync with random payloads including hekate; however, the most common desync occurs from Linux.

Howe about playing something like psnes?