Macbook Air 11" A1370 820-3024 only white screen

[boxer]

Hello!
I have an Macbook Air 11", A1370 820-3024 which turns on, fan is spinning, it chimes but only has an white screen!

I already checked all power rails => all are ok
The LVDS connector + supply is also ok.
Also no Video on external thunderbolt
SMC Reset etc, trying to boot from external USB unsuccessful.
I also checked the complete board under the microscope rigorous without any result.

I have spent already a lot of time.. but at this point I am very clueless.

Maybe some of you has some idea or hint?
THANKS!!!

 

[Alan.L]

to me these 3024 known for bios failed. do you have donor board that has a bios to test it out?

 

[boxer]

No I dont have... you mean exchanging the bios IC?!

 

[Alan.L]

yes, of course.

 

[dukefawks]

Do NOT touch the BIOS!

Did you remove the SSD?

 

[boxer]

Yes, I also tried erverything without the SSD.
I also noticed that I cant do any PRAM reset.

 

[dukefawks]

Removed everything and all cables? Just bare board and a known good LCD. Even the LCD can cause issues.

 

[2andrewd]

Your describing the EXACT symptoms i experienced when i did fuck with the bios... I didn't clean the me region properly, both times i did so i got what you have. Obviously deferred to the advice above however

 

[boxer]

Update from my side, I replaced the BIOS chip woth a new one. Now it boots, I can start the OSX install menu etc. But the macbook just turns off during the install. I tried everything, resets etc... always same behaviour... macbook turns off during install!
Any ideas?!

 

[dukefawks]

Read original chip and post the binary here.

 

[boxer]

Ok, thanks... I will try to do that!