LG PLASMA DU-50PY10

[cetrone]

I started working on a Plasma DU-50PY10.
Symptom: Shutdown with red led on front.
When main power button is pressed relays click on and off.
When the power button on remote is pressed red led changes from red to green for a few seconds and then back to red.
I called LG and the technician said:
You need to put a load on the power supply connector that goes to the YSUS and ZSUS boards. one 100 watt light bulb on VS and gnd and one 100 watt light bulb on VA and gnd. If the red led goes to green and stays - change the Ysus and Zsus boards. I did the test and the led did not stay green.
I have the DU-50PY10 service manual but, there is no schematic of the power board. The power supply Part# 3501V00179B cost $275.00 at MCM electronics. Anybody have any suggestions?
I'm not 100% sure it's the power supply board.