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[help] 820-01958 dead: 20v not switching
- Thread starter phantom
- Start date
according to this post
boards.rossmanngroup.com
i've check all voltages: ALL THE SAME OF THE POST!
PP1V2_AWAKE 1.2V
PP1V8_AWAKE 1.8V
PP3V3_AWAKE 3.3v
PPVDDCPU_AWAKE 0.755v
PPVDDCPUSRAM_AWAKE 0.802v
PP0V8_SLPS2R 0.800v
PP1V8_SLPS2R 1.8v
PP1V25_SLPS2R_SMC_AVREF 0.234v
PP1V1_SLPS2R 1.1v
changed u4780, now i have 1,25v on PP1V25_SLPS2R_SMC_AVREF
reprogrammed eeprom
still no boot: here the usb meter
www.dropbox.com
ppbus_g3h is "unstable" because it goes from 12,31 to 12,4 to 12,59 without any logic and come back to 12,31 (with charger and battery). with charger only, stable at 12,31
all other voltages, still in loop: from the right voltage to 0
820-01958 DFU problems
This arrived fully functional. User wanted their drive erased and a new OS installed. Booted into OS recovery mode and erased the SSD. During the erase process the screen went black but then nothing else happened. Normally it would turn back on and start internet recovery process. When trying...
boards.rossmanngroup.com
i've check all voltages: ALL THE SAME OF THE POST!
PP1V2_AWAKE 1.2V
PP1V8_AWAKE 1.8V
PP3V3_AWAKE 3.3v
PPVDDCPU_AWAKE 0.755v
PPVDDCPUSRAM_AWAKE 0.802v
PP0V8_SLPS2R 0.800v
PP1V8_SLPS2R 1.8v
PP1V25_SLPS2R_SMC_AVREF 0.234v
PP1V1_SLPS2R 1.1v
changed u4780, now i have 1,25v on PP1V25_SLPS2R_SMC_AVREF
reprogrammed eeprom
still no boot: here the usb meter
Dropbox
www.dropbox.com
ppbus_g3h is "unstable" because it goes from 12,31 to 12,4 to 12,59 without any logic and come back to 12,31 (with charger and battery). with charger only, stable at 12,31
all other voltages, still in loop: from the right voltage to 0
Last edited:
SSD voltages can be recovered many times in DFU restore.
You should get the board working with charger alone; testing on the desk, out of case.
I don't really expect this board to be repaired...
You should get the board working with charger alone; testing on the desk, out of case.
I don't really expect this board to be repaired...
Yeah, these voltages can be recovered sometime, IF DFU completes successfully; is not the case here...
There are so many things that can cause such behavior.
Is impossible to make a list with all involved components.
As I many times said, this is not an exact science...
Is impossible to make a list with all involved components.
As I many times said, this is not an exact science...
i understand, but i dont' want to give up....maybe i should open a new thread and write " i don't know the history of this devic: it switch to 20v but it seems in boot loop: what can i check"
maybe restart from the beginning would be usefull...
for example i think i MUST HAVE some power rails before to boot...is it possible that it does'nt boot because i miss some rails?!??!?
maybe restart from the beginning would be usefull...
for example i think i MUST HAVE some power rails before to boot...is it possible that it does'nt boot because i miss some rails?!??!?
Before getting power for Intel side, SSD should get its voltages.
You may have problems with T2, U7800, or SSD.
You may have problems with T2, U7800, or SSD.
If no voltage, check them in diode mode too.
As I said these voltages depends by T2 and U7800.
But even one corroded trace, or component can block them.
As I said these voltages depends by T2 and U7800.
But even one corroded trace, or component can block them.
You can see them pages 70 & 71.
Generated by U7800 and U9060.
Generated by U7800 and U9060.