Vizio 42" Plasma - PDP42X3U400

[jnbeckham]

I have a 42" Vizio Plasma that I picked up from someone who didn't want to go to the trouble of trying to fix it. I'm hoping to get some help troubleshooting the set myself and hopefully end up with a watchable TV. Other threads here have given me some possible avenues (perhaps too many for a newbie).

Behavior: The set will not turn on. There is no standby light when plugged in. There is no relay "click" when the power button us pushed. According to the previous owner no "pop" was heard when the set went bad, it just went black.

Visual Inspection: Upon visual inspection, there do not appear to any bulging capacitors or blown fuses on any boards.

Testing: I have done minimal voltage testing on the power supply (6709900019a | 68709M0031A/5) thus far and could use some help here due to my inexperience. The only voltage I can confirm is 5V standby on pins 3 and 8 of the P800 13-pin connection to the main board.

I am attaching a photo of my power supply. It's not the greatest picture in the world so I am also linking to another photo of the same board for reference.

[jnbeckham]

Re: Vizio 42" Plasma - PDP42X3U400

Update: Following the lead on another thread I saw here, I unplugged the main board (0171-2272-2233) and plugged the set in. Immediately heard a relay click, the power came on, and the screen glowed gray.

Attached us a picture a main board identical to the one in my set; It is not the actual board. My logic might be too simplistic, but I am assuming this means I have a bad main board. If so, is the best option simply to replace or should I continue to troubleshoot and try to repair it?