820-2530 no display

[nate8organic]

Im a new repair tech and i am getting experience on older boards, wondering if anyone can help me out.

I have fan spin and green light but no display, i have back light voltage, and i checked the screen with a flashlight and there was no image

i cleaned corrosion around G4300, G9440, and L7320.

i replaced u5000 as it was not giving 3.4v on pin 2

i tested c7565 and was getting 1v for ppvcore_s0_mcp, and i also tested l7400 and got 0v for ppvcore_s0_cpu

thanks for reading
-Robert

 

[larossmann]

What is on pin 44 of U7400?

 

[2informaticos]

"G4300, G9440"
I don't see these on schematic...

Do you get correct voltages at L7320, L7620, L7760?
3V at ALL_SYS_PWRGD?

"i have back light voltage, and i checked the screen with a flashlight and there was no image"
Something strange there.
Why should you need flashlight if has backlight???
Please explain correctly the symptomps.

However, no CPU VCORE, so board cannot work at all; no backlight/image, nor USB activity.