So the SYS rail provides VIN for for the EN IC (as far as I remember), which regulates 3V3PDR (the “ENXX” IC can be found below the realtek IC)
3V3PDR is connected to pin 6 of the M92 IC, if you measure 0V here after promting the console to boot, then something must be dragging down the 3V3PDR, I would measure the resistance to ground here.
Either that or the EN IC has failed or it’s not being told to turn on as a result of another fault.
So afaict the fault is most likely going to be an issue with the M92 or the soldering, the USB port or the BQ IC and maybe even the fuel gauge.
If the measurments above are good then I would start by removing the M92 IC and seeing if the console will boot battery only and if by removing the M92 IC 3V3PDR returns.
Alternatively, Hekate makes this process quite a bit simple and strips out a lot of this manual work.
That’s fine
I’m going to disregard this measurment as low end meters have trouble taking accurate in circuit readings here (even some flukes)
This is interesting,i’m getting 5V on pin5 and 0V on pin6 of M92,with battery and 5v usb charger connected.
Usb detector shows 5v and 0 steady amps,so i think it’s not booting at all right?Soc is cold too
Aww ok thanks did not know about that,btw im using a Brymen 235 from EEVBLOG,not the top like FLUKE but i think it’s a good one
Pin 5 is unrelated to pin 6 (3V3PDR). So with 0V on pin 6 (3V3PDR) but with the SYS rail present you should ordinarily see 3.3V here.
CPU(0) (or boot CPU if you prefer) is active, which afaik would/should enable the EN IC.
So you should measure the resistance to ground on pin 6 of the M92 IC and we’ll see if something is dragging this rail down which might explain the problem.
Though it could be any of the other faults I mentioned previous.
It’s a quality meter, but just as prone to false readings on this rail, it just so happens that low end meters meters measure this particular rail (1V8PDR) incorrectly more often. Don’t worry about it, the rail is fine and fits what I expect with your meter type
with only the charger connected i get 0,6V on pin 6,but when i connect battery i get 0,dunno if it is interesting.
I also measured usb-c connector pads in diode mode,and values are good except the 2 pins in the middle,that reads strange higher values,not 0.775V but about 2,5-2,7V,is that normal?
Just a heads up calvins charts are diode mode measurments, no battery/power should be applied, just in case that’s whats going on here.
In terms of resistance (again no power/battery applied) your readings are too low, you should be reading high megs, typically around the 5M mark though it depends on the board revision.
Though, this is the problem with taking random measurments here and there, they don’t really say much as everything is interconnected and a fault elsewhere will have a knock on impact somewhere else (if that makes sense)
What’s your voltage readings on the points I highlighted above, maybe that can shed some light on whats happening
yes i did all measurements with battery and charger disconnected
Do I have to reconnect all the cables and press the start button on the side of the body? I’m not sure I understand, can you explain the correct procedure for the test? Really thank you very much for the time you are dedicating to me
So by “prompt” I just mean pressing the power button, or using the USB to tell the console to turn on. If your pretty confident the USB is fine then it’s simpler to just use that to do it. The board and battery alone are enough for these tests nothing else needs to be connected (aside from the USB initially)
Alternatively you can connect the power button, vol +/- flex and use that instead of the USB.
Or you can bridge the corresponding pins of the flex connetor directly.
Or there is a testpad somewhere, though i forget where off the top of my head.
Good spot those ICs are a real pain to peak under because of the surroundings
Though this is almost certainly not going to affect your previous measurments so don’t think that’s the primary issue here (because the ball/pad is open if anything and not shorted to anything else)
So see how it says “active low” it means pull low to activate essentially.
You’d just bridge either of those points (take your pick) to ground to “press the power button” which is effectively what your doing when pressing the power button, pair of tweezers will work.
Will say though, I’ve not verified a lot of the TP listed on this site, so do it at your own risk, or buzz these points to the power/vol flex connector and see if they are the same as the pin here to verify if your not sure
Pin 6 of the M92 is connected to 3V3PDR (the big cap I highlighted near EN IC)
The left side of the resistor I asked you to measure is a 1.8V enable signal (which is in sourcing it’s voltage by way of 1V8PDR but is not a direct connection to it) from the SoC to tell the EN IC to enable the 3V3PDR output.
It’s got a heartbeat it’s at least partially ok, but no guarantees just yet
Right, you should see after prompting the console to boot 3V3PDR at pin 6 now, which means your EMMC and other ICs on this rail will now have power unlike before.
You might wanna try now with the bl/screen connected
Why your USB is/was not prompting the console to boot earlier though is another issue.
If it’s not a USB connector issue then think it’s going to come back to one of the three ICs i mentioned earlier. I hope you’ve got a jig on order it’s so much easier
those ICs are a real pain to peak under because of the surroundings 
it’s at least partially ok, but no guarantees just yet
it’s so much easier