820-3208 chimes no video/image/backlight

[Aivaras]

Macbook chimes but no image or backlight.

ppvcore_s0_cpu_ph1 - always present
ppvcore_s0_axg_r only present for 10-15s then drops to 0v and never comes back.

What should I look for first?

 

[2informaticos]

AXG voltage is not always required; unless high load graphics is detected.

First confirm 100% USB activity.
That means board doesn't get stuck after chime.
Do few PRAM reset, just in case.

Did you check external video?
Did you try another LCD assembly?
Any history available, some liquid signs?

 

[Aivaras]

Works another LCD. Thank you.