My LG 50ps3000 zsus - LG 50PX5D 50 in. Plasma HDTV

Just replace your tv power board.
LG EAY62171201 EAX63330001 3PAGC10038A-R PSPL-L014A POWER SUPPLY UNIT https://www.abctay.com/lg-eay62171201-eax63330001-3pagc10038ar-pspll014a-power-supply-unit-p-1875.html

Lg 50ps3000 manual can be found here:

http://www.lg.com/uk/support-product/lg-50PS3000

There are so many reasons for this fault. Can't point out just one or two. A through checkup should be done with your Plasma Display. Contact any experienced service technician. The work is a skilled one; not a user repairable.

Just contact the nearest authorised service center for LG at your town. They only can provide it to you. It will be best to replace LCD panel by company technicians. There are so many adjustments to have done, after Panel replacement. You have to enter the set's service menu options to do this. It is really a very skilled work.

What you need is an exchange or repair of your ZSUS board:
http://www.coppelltvrepair.com/p/485/lg-42pc3d-zsus-exchange-service-for-dark-grainy-screen-problem

My 50inch plasma LG tv has no picture only sound.

Might be the power supply board. Check for a solution here: http://www.coppelltvrepair.com/p/795/lg-42lb4d-power-supply-board-repair-serivce-for-totally-dead-not-powering-on-or-shutting-down-tv

zsus board is faulty disconnect zsus supply set should come on

code 1280

LG 42" Plasma TV 42PX3DCV Parts - YSUS ZSUS CTRL Part Number (set): 6871VSNB03E Part Numbers (individual): 6871QYH036D, 6871QZH041B, 6871QCH053G Part Number: 6871QYH036D Description: PCB ASSEMBLY, DISPLAY YSUS ASSY 42V7 FOUND THESE ON THIS: http://cgi.ebay.com/LG-42-Plasma-TV-42PX3DCV-Parts-YSUS-ZSUS-CTRL_W0QQitemZ110086231102QQihZ001QQcategoryZ116199QQcmdZViewItem HOPE IT HELPS