820-00426 stuck on apple logo

[Don Anton]

Hi
this is very clean 2015 retina 15" logic board. No liquid dmg.


This goes about 75% and stuck on apple logo.

I disconnected everything and even only with board and the screen still same result.

booting with osx installation drive it boots and can install the new osx. after installed it stuck same as beofre.

Tried with externeal usb SSD osx , same result.

Any help greatly appreciate

 

[2informaticos]

Try clean ME first...

 

[JohnB8812]

Try new battery first!!! Bad battery will cause no boot on these. Sometimes has to have a good battery hooked up to boot

 

[Don Anton]

Hi thank you for your reply. Did clean me same situation. any clue?

 

[2informaticos]

Tried known good battery, as John mentioned?

 

[Don Anton]

hi,

I'm trying with our the battery connected. still stuck on apple logo. I have anothe same board which works fine with the same topcase and the battery.

 

[2informaticos]

Did you clean ME with Medusa?

 

[JohnB8812]

Make sure to rule out all housing issues (I/O board and cable, trackpad, SSD, etc.) And yes what did you clean ME with?

 

[Don Anton]

No i removed the bios and cleaned the me region using ezp bios reader. I checked the board puuling out board by itself with a screen and usb mouse only. still same

 

[2informaticos]

You MUST clean ME region properly.
If you don't have Medusa programmer, search the forum; you'll find how to do it in manual way.

 

[Don Anton]

HI 2info.
Finally i got the Madusa 2 and did clean me successfully. Still the issue is there stuck in apple logo. how ever it boots with OSX install usb to install screen. Tried with external usb Hdd same issue.
Apple logo stuck about little over to 30% of loading.

 

[Don Anton]

Also if the GPU is thr problem will this boot with OSX install usb?

 

[2informaticos]

"it boots with OSX install usb to install screen"
Do you mean machine enters to OSX desktop using preinstalled USB pendrive?
If so, switch to dGPU (try gfxcardstatus) and see if crashes.

 

[Don Anton]

Hi, NO it does not boot with preinstalled USB. What i mean It boots with Any USB bootable drive to diskutilities and OSX install screen.

 

[2informaticos]

Then is possibly GPU issue...