820-3476-A

[2informaticos]

Be aware, resistor value measured onboard is not accurate; especially for high values (K/Mohm).

Change U7400...

 

[iFix]

I changed U7400 but I lost PP5V_S4, When the original U7400 is on the board i have PP5V_S4 and all measurements as mentioned before, with 2 other U7400 i lost PP5V_S4...Green and orange light still comes on in any case...

 

[2informaticos]

Did you test in SMC bypass?

Remove R8168 and try again.

 

[iFix]

Removed R8168 and smc bypass, still same no change

 

[2informaticos]

Test removing Q8150 too.

 

[iFix]

Same thing

 

[2informaticos]

Check all components around U7400...

 

[iFix]

I checked all resistors taken out from the board and the only one around U7400 that was lower resistance was R7416, instead of 100k it's 60k...

 

[2informaticos]

What is actual diode mode to ground at L7430?

Check again U7400 voltages; pins 12, 17, 16, 6, 1, 5.
Just in case, change C7425.

 

[iFix]

Just got back to this one...

L7430 diode it's 0.085 and also on C7425. But in the meantime before I saw your msg I reballed the SMC and the laptop started, but no picture just the fan spinning fast. I would reprogram the Bios to see what's gonna happen.

 

[2informaticos]

Which voltages get you now, in big coils?
PLT_RESET_L comes high?

 

[iFix]

PLT_RESET_L it's 3.3v now. Also i had one resistor moved near the Bios Chip. But, also i forgot from before i had taken out Q8150 and just saw it's not on the board... I'll solder it back and try again.

 

[iFix]

I've soldered all back on the board, now when i plug it in fan starts spinning fast and increasing and no image... fast slows down after 1 min and speeds up again afterwards

 

[2informaticos]

Did you solder that resistor near the BIOS chip.
Check all SPI Bus Termination resistors and their traces.
Clean J6100, if needed.

Just in case, try known good BIOS.