LG 50PT350 Dead....ish

[Michale32086]

Have a nice LG Plasma 50PT350

Normally, I wouldn't expend much effort to get a plasma going. But it's in nice shape and my inventory is sparse..

Symptoms are it was as dead as a doornail. Absolutely no voltages, no relay clicks, no power LED indicator or Control Board LED indicator came on.. I assumed Power PCB..

Got a new one and now things are weird..

When everything is hooked up, I get 0V on the VS point (green)..

When I isolate the Power PCB with no hookups other than the power plug and the Main Video, I get 60-ish volts that start counting down til about 30v and then jumps back up to 60V.. Rinse and repeat..

That's on the VS line.. Now when I hook my meter to the large caps (red) I get steady 390V whether the power PCB is isolated or not..

I have replaced the Power PCB, the Y-SUS and the Main Video Board, but I can't say for certainty that the boards I replaced them with are working. I assume so but can't swear to it.

Any hints as to what to look at next???

Thanx in advance..

[akis24]

Re: LG 50PT350 Dead....ish

hello if you unplug the output connectors from the power supply board the voltages should be present if this is not the problem is related to the power board in any case from what you write you should still have the 5 volt voltage present with the stand-by LED which come on said this follow the advice at the link that I apologize for bad English.
http://tomtechtodrepair.blogspot.com...c-and-diy.html

[akis24]

Re: LG 50PT350 Dead....ish

I hope I haven't broken any forum rules by posting the link.