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Pete
Pete, Electronic Engineer
Category: TV
Satisfied Customers: 18115
Experience:  Over 16 years of experience installing and repairing electronics.
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I have a Plasma TV LG model 42PJ350. When powered on, I only

Customer Question

I have a Plasma TV LG model 42PJ350. When powered on, I only get a black screen with backlight. No menu or options will come up on the screen.
Submitted: 2 years ago.
Category: TV
Expert:  Pete replied 2 years ago.
Hello,
I am Pete, and I'll be happy to assist with your question today.
Check if you can hear any sound.
If you can hear sound ok then it is likely a problem with Y- or Z-sustain.
Further testing of these boards will help determine where the fault lies - the faulty board can be replaced.
Customer: replied 2 years ago.

I don't hear any buzz from the speakers.

Expert:  Pete replied 2 years ago.
Have you tried connecting different input sources and flicking around with the remote control?
Customer: replied 2 years ago.

TV is non responsive besides the power on. Cannot switch channels, get menu, etc.

Expert:  Pete replied 2 years ago.
If there is no audio or other responsiveness from the TV, then this is more indicative of a power supply board fault.
Try swapping in a replacement power supply board.
Customer: replied 2 years ago.

Even though it powers on to backlight and all the voltages check good?

Expert:  Pete replied 2 years ago.
Yes, the power supply board has several different outputs, and if just one section of it fails it can result in the symptoms you are experiencing.
Customer: replied 2 years ago.

OK, looking for replacement on ebay.

Think it would be worthwhile to purchase a repair set w/ parts? I'm very good at soldering but not sure if these are reliable to fix the problem.

http://www.ebay.com/itm/221551034989?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Expert:  Pete replied 2 years ago.
A repair kit will contain some parts that commonly give trouble on this board, and may work in 80% of failures. It will take a little bit of time to fit the parts, so if saving money is your priority then a repair kit is probably worth the gamble. If you need the TV running reliably again as soon as possible, then a replacement board would be the better option.
Expert:  Pete replied 2 years ago.
Hi Steve,
I'm just following up with you to see how everything is going. Do you need any further assistance?
Let me know,
Pete.
Customer: replied 2 years ago.

I've got another board on order and will let you know results when installed.

Expert:  Pete replied 2 years ago.
Ok, thanks for the update!
Customer: replied 2 years ago.

Got the board in yesterday. Installed this morning. Now it clicks, back-light turns on for 1-2 sec and then it cuts back off with a click.

Expert:  Pete replied 2 years ago.
Where did you obtain the replacement board from?
What are the output voltages testing at?
Customer: replied 2 years ago.

Can't find any new for this unit. Got off ebay, listed as used pulled from working unit.

Stdby goes .4-2

Va will jump to 188 then it clicks off

I've tried unplugging all other boards expect the power coming in and I still get no stdby. I was worried another board was also bad, but the fact that it still reads 0 when nothing else plugged makes me wonder if I got a dud.

Expert:  Pete replied 2 years ago.
Hi Steve,
You should be getting a standby voltage from the PSU board. If you are not, then there is likely a fault on that PSU board.