Samsung 42" Plasma PN42C450B1D

[tslim429]

I have a Samsung 42" Plasma approximately 3 years old (PN42C450B1D). Over the past month while watching TV, I would periodically lose the picture to a black screen, but the sound would continue to be played. Turning the TV off and back on would typically fix the problem temporarily. The more I watched the TV, this symptom got progressively worse. The TV is now to the point that it will not even turn on. I push the power button, here a click like it is attempting to turn on, then it immediately clicks again and turns back off. I have removed the back cover and looked over the capacitors, none seem to look bad/burnt/busted. Please help me diagnose this TV, I'm not ready to part ways just yet. Thanks!!

[capkid]

Re: Samsung 42" Plasma PN42C450B1D

Try disconnecting the X-main to see if the TV stays on and you get sound (you may have to blindly change inputs with the remote to find one with sound). Also, check your VS and VA voltages with the X-main disconnected. If you get sound and your VS and VA stay up, STOP TESTING!!. Your X-main is faulty and it needs to be replaced. Warning: Don't try to repair it. Many of us have been down that long, windy road to oblivion.

You're going to want to be very careful testing this TV, since the Y-main and X-main are chained together. You could blow a Y-main if your X-main is faulty or vice versa while testing.

Here's a thread: https://www.badcaps.net/forum/showth...hlight=samsung

Here are my thoughts on these thin Samsungs - may not be applicable in all cases, as each model is different: https://www.badcaps.net/forum/showpo...74&postcount=5

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

Please bear with me as I am new to electronic repair to this extent, the X-main is the top right board inside of my TV (see attached picture) correct?

When you say to try disconnecting the X-main, do you mean disconnect all 4 connectors and completely isolate it?

[tom66]

Re: Samsung 42" Plasma PN42C450B1D

X-main is orange board on right here
https://www.badcaps.net/forum/attach...3&d=1374374251

Disconnect the grey power connector, everything else left connected.

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

I tried disconnecting the X-Main and the problem persists...turns on and back off with no Samsung Chime. I tried disconnecting the x-main and the y-main and powered on, i heard the Samsung Chime this time and the TV stayed on. Does this mean my problem is within the Y-main or Y buffers? Of course the battery is dead in my voltmeter, I will have to run to the store before checking voltages

[tom66]

Re: Samsung 42" Plasma PN42C450B1D

Replace the X-main and Y-main. The buffer does not usually need replacement.

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

Replace the X-main and Y-main. The buffer does not usually need replacement.

Thank you, where is the best place to purchase replacement parts?

[tom66]

Re: Samsung 42" Plasma PN42C450B1D

ShopJimmy, eBay are two favourites but there are many more, just look up the LJ96 number on board.

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

ShopJimmy, eBay are two favourites but there are many more, just look up the LJ96 number on board.

Thanks, I am only seeing an LJ41 and an LJ92 number

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

Thanks, I am only seeing an LJ41 and an LJ92 number

Think I have it figured out, $50 fix would be nice!

[tom66]

Re: Samsung 42" Plasma PN42C450B1D

LJ92 then... my error.

[capkid]

Re: Samsung 42" Plasma PN42C450B1D

If they're available at a reasonable price from ShopJimmy, I'd go with them. Their parts include a 180-day warranty.

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

Ordered boards from shop jimmy for about 55 bucks total. They came in today, took about 10 minutes to swap them out, plugged her in and sure enough she fired right up. Now I get to walk around the rest of the day bragging about my accomplishment haha, thank you all for the help and saving me some money.

[capkid]

Re: Samsung 42" Plasma PN42C450B1D

Great to hear. Tom would know best, but you may need to update the firmware on this TV to prevent a future failure.

[tslim429]

Re: Samsung 42" Plasma PN42C450B1D

Great to hear. Tom would know best, but you may need to update the firmware on this TV to prevent a future failure.

That's something else i don't know much about with a TV, how is the firmware updated? Is it attached to a PC somehow? Can you link me to a thread or website that might walk me through it?

Thanks!

[capkid]

Re: Samsung 42" Plasma PN42C450B1D

Here you go: http://www.samsung.com/us/support/ow...N42C450B1DXZA?

[TheRoop]

Re: Samsung 42" Plasma PN42C450B1D

I have the same TV with the exact same issue. I see where you guys identified the X main and they grey power cord to unplug. Could you please identify where the Y main is?

I tested with X main unplugged and same issue (clicks but doesn't turn on at all and just gives up). I will test with both unplugged next, and based on what I've read above, if I hear the Samsung chime then I need to replace both boards?

Thanks much.

Cheers

[capkid]

Re: Samsung 42" Plasma PN42C450B1D

The Y-Sus is on the left side when you're viewing the TV from the back. A long, vertical board is attached to it.

[fatcattara]

Re: Samsung 42" Plasma PN42C450B1D

Hello All,
Mine is a PN42C430A1D, the TV will turn on, will have sound and picture for 5 - 10 minutes and then the screen goes black with the sound still on. If I power down and wait some time, the whole procedure will be repeated and again a black screen. Since the set is a "hand-me-down" from my daughter, I would like to try and repair the set. Any tips or pointers please?

[tom66]

Re: Samsung 42" Plasma PN42C450B1D

When the screen goes blank, can you see a faint glow from the screen still?