Hello! I have a Nintendo Switch (Patched) that doesn’t power on. I checked MAX outputs and I can see that I don’t have VCC_2V9 and VSYS is 3.8V, not 4.2V. Where should I look for the fault? Right now I am at a dead end. Thanks!
VDD_1V3 is also missing
Ignore anything from any wiki which you;ve read, it’s likely just going to lead you down the garden path. that includes all the bad info, poor naming conventions, dangerous advice etc etc 
If you did follow any dodgy advice from such a source though do lemme know what so i can get a better picture of any potential issues caused and better help 
SYS rail probably fine, pretty sure it’s just regulated battery output until plugged in if i recall, but you can measure resistance to ground on this rail if you want just incase and let me know the reading.
Is this a Mariko revision by any chance? 1V35 on Maiko being missing is typical and could be a number of things
Switch keeps on 0.300a, doesn’t do the second boot.
It’s a Mariko Patched.
What do you need to know so you can help me? Measurements, values, etc.
Thanks!
Mariko and patched are two different things different SoC variants.
Just as i said bud.If you followed a guide or that dodgy wiki (as i suspect) let me know what you have or haven’t done with this board so far, practical or no, the board/consoles history etc.
Given your missing 1V35 and this is a presumed Mariko rev then i guess I could take a look at the fuel gauge and a few other common points of interest, so if you want just upload some images of your board to an image host and format the line like >> imgur (dot) com/youimageuploads
The areas of interest for pics, fuel guage, M92, USB, BQ areas and front and back of the board as a whole in as good a quality as you can, in good natural lighting. A good rule of thumb is if i can’t read the part number of the ICs on the close up pics then the quality ain’t good enough for me to check.
And as I say your welcome to measure resistance to ground on SYS (or any other rail for that matter) if you want and let me know the reading (good first step for anyone regardless) - black probe on ground, red on rail in question. SYS for example can be found at the 2R2 coil near BQ IC.