macbook pro 13 2016-2017 820-00840 stuck on apple logo

[dellxps15]

hi i got this macbook that was stuck on apple logo. tried ssd on another board and it work perfectly.
tried also pram nvram reset, smc reset, safe mode, verbose etc etc but always same thing: laptop power on with chime... stay on apple logo for like 60 seconds and then reboot.

today im getting t3 screw and take board apart, but it seems to have no liquid spill or similar. top of the board is perfect and like new....

anyone got that similar problem? bios or what ?

[dellxps15]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

t3 arrived and on the back of the board all looks ok.

things ive done: swap bios from same board code.... it give black screen

with original bios, usb lstick light blink, but i noticed that i have apple logo even without any usb or ssd connected, like it's booting but obviously it cant because there are no boot device connected.
on all other board apple logo comes only if boot divice is connected.

i suspect some capacitor on ssd connector is shorted...

all voltage are ok. cpu vcore is 0.63 volt on bot that and other working board.

edit: tomorrow ill try a bios with clean me

[dellxps15]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

tried bios with clean me but still black screen no question folder mark and no os loading with ssd . after 60second pc reboot itself.

with original bios it give apple logo as soon as display turn on. with clean me bios it give black screen and no folder question or so.. .act like dead.

[mon2]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

Review each and every power rail - especially the SSD power rail.

Also see attached for a chart of inductance to ground readings. Remove all power before taking measurements. Meter in lowest resistance scale.

[dellxps15]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

hi mon and tnx for reply. none of that measurement give me low value. those on first picture show an over ol scale when measure and voltages are good and present there.
the only one reading different is l7900 that i resistence mode 0-200 scale give me 50 value, but there is around 1 volt there when pc is powered on.

update: just discovered that first time i give power to board, fan spin, ppvcccpu_sog_ph1 start at 0,9 volt then drop to 0,63volt ( i see on another videovideo that around 0,6 volt are perfect after volt drop), while when board start reboot cycle volt here start again from 0,9 and then drop to 0,78 and no more fan spin.

pp5v_s0 always present when board is on. goes off just after board reboot then comes on again. same for all other voltage 1,8s0 3v3 s0 3v3 s5 3v3 s4

[Simplebeans]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

hi i got this macbook that was stuck on apple logo. tried ssd on another board and it work perfectly.
tried also pram nvram reset, smc reset, safe mode, verbose etc etc but always same thing: laptop power on with chime... stay on apple logo for like 60 seconds and then reboot.

today im getting t3 screw and take board apart, but it seems to have no liquid spill or similar. top of the board is perfect and like new....

anyone got that similar problem? bios or what ?

What readings do you get on a USB tester during this issue?

tried bios with clean me but still black screen no question folder mark and no os loading with ssd . after 60second pc reboot itself.

with original bios it give apple logo as soon as display turn on. with clean me bios it give black screen and no folder question or so.. .act like dead.

I would be inclined to revisit this, when you changed the bios you need to get the machine atleast getting to the apple logo to see if its produces the same error. This way we can rule out the bios.

[dellxps15]

Re: macbook pro 13 2016-2017 820-00840 stuck on apple logo

What readings do you get on a USB tester during this issue?

hi tnx for helping. reading was up to 700mah then down to 490mah as pc was working just fine.

I would be inclined to revisit this, when you changed the bios you need to get the machine atleast getting to the apple logo to see if its produces the same error. This way we can rule out the bios.

with new bios it never get to apple logo and as i write with older bios it get apple logo even without any usb or ssd installed, and on a working board, when there is no boot it doesnt give apple logo but usual question folder.

owner need fast fix so i put a working board in it and take one component from that board to the other and need part to get on me from china.