Pro Vision HQL320WR - Stuck on Stand By

[electro76]

Hello Badcaps,

I got this Pro-Vision 32" LCD with 'LG Panel' as it won't turn on anymore and they wanted to throw it away.
The stand by led is on but strangely it's lit orange color as if both the red & green are on.
Checked the voltages on power board - all show zero but
they come back to life when 1 specific conn disconnected from the main DVI/VGA board (only needed to remove the cable marked with 'I' to see all voltages come back).
The P106P connector pinout is: GND, +5V, ST_BY_5V, +9V, MAIN_ON, LVDS_ON, GND.
Not sure but it seems that the main board does not send the on-off signal to power board or causing all voltages to drop to zero.
I also noticed that half way insertion of P106P marked conn, the LED lights in red only (and not a bi-colored orange).
When stand alone power board is connected to mains these 3 voltages do not exist:
LVDS_5V
MAIN_ON
LVDS_ON
All other voltages appear OK:
+24V
+3.3V
+5V
ST_BY_5V
+9V
+33V
+15V

Can you please advise schematic for this set and what to check next?
I would suspect a main board issue but cannot debug without a diagram.