Macbook A1398 (820-3787) No Display

[2informaticos]

"i get 4.9 V initially and then a continuos 3.9V at the pins.
Also i get 2.8V at LCD_HPD."
What is actual state of these voltages?
LCD_HPD steady high?

 

[Instafixx]

LCD_HPD not steady high.

The situation is same. for the other Pins

 

[2informaticos]

Get 5V at pins 28-30 now?
At least when machine chimes.

 

[Instafixx]

I an getting 4V now when the machine chimes at Pins 28-30

 

[2informaticos]

Post all U8300 voltages.

 

[Instafixx]

Today i do not get any chime. But i still get the 4V at Pins 28-30 till there is fan spin.
The fan spin is also erratic - happens sometimes .

PPBUS is stable at 12.55V.

Now there is absolutely no fan spin (Both with or without battery)

U8300 - all zero now obviously

 

[2informaticos]

Do you get CPU core?
What other basic voltages missing?