This means there are LETHAL VOLTAGE INSIDE and not considered user serviceable.
With that said, you want to track down its service manual. I see a lot of Internet users hope some TV tech will answer how to fix a set but no tech I know will commit to "it's this or that."
But a lot of good info is out there for serious folk that will hunt down the service manual. If you find folk that won't do that, it's best to send them to the maker to ask where to get it fixed.
More finds at https://www.google.com/search?q=shopjimmy+plasma+repair
LG model 60PZ950 from 2011. Red standby light is on, I try to power on and it begins by lighting the blue (on) LED's and after a few seconds, it stops and returns to the red standby, with no picture or sound. Any help?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic