This board boots and has display on external monitor. Can't tell if it has video on LCD screen. Has EDP_BKLT_EN at 3.3V. Has PP5V_S0SW_LCD at 5V. 0V on PPVOUT_LCD_BKLT. Is this just a U8400 replacement? I'm trying to rule everything else out before just replacing it. The board was hit by liquid in that area. C3504 was ugly and needed replaced. Other than that it looks pretty good. Diode measurements are coming up normal.