I have a 50PQ30 top half of picture goes away.

I have had a few HP printers that seem to get confused when something doesn't go according to plan. I eventually learned to switch everything off and walk away for half an hour.

is the check engine lite coming on

Check and replace its T'Con [Timing Control] board.

If you wish to get some details; visit the site linked here. Pull up older posts.
https://electronicshelponline.blogspot.com/
Line faults & possible causes to LCD & Plasma screen are given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD & Plasma screen are similar, irrespective of its brand and screen size.

Half of it goes away in the first 30 years, leaving 0.5mg. Half of that goes away in the second 30 years, leaving 0.25mg. Half of that goes away in the third 30 years, leaving 0.125mg after 90 years.

If the z-sus board burned again unfortunatley it means the PDP (plsma panel) is defective. Sorry for the bad news : (

Hello: Seem you are in zoom mode, try hitting the format putton on the televisions remote and if you are using a cable box and using HD check for a picture format or aspect button on it also. You will want to be on 1080i normal or stretched. The cable box and television will use different modes for aspect, try using only one of the remotes when changing aspect ratio buttons or screen size.

remove the back wall leave the unit to run half hour open and see if coil have frost all the way from the top of the coil to the bottom if the coil is full you have adefrost problem could be your timer defrost thermostart or heater

your tv is having a problem of more than one component .to get rid of the problem u should rectify your vif horizontal and vertical sections

I have a 51" magnavox plasma. after about one half hour the bottom half of the picture goes black, and u can still see the top half of the picture. what can that be