Hi,
Your unit is a Plasma TV, it hasn't a bulb.
The symptoms you've described is caused by faulty
upper Y-scan drive. It is a rectangular board located at the left side of your unit(if you are facing at the back panel). You have to replace this board to resolve the issue.
You can do it yourself because no soldering required, let the unit unplug from the outlet for 1 hour to drain the voltage from the power supply before you replace the board. Pull-out the connectors from the existing board, put-in the new board, re-insert the connectors and you're done.
I would advice you to check the actual part no. of your board that is printed on the white sticker on the board itself to get the right replacement online. Click the link above to see how it gonna looks like...
Hope I helped you.
Have a nice day!
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