LG 42pt350 A little help.

[elchochito]

Re: LG 42pt350 A little help.

It sounds like your Z-sustain is bad then.

To test:

Unplug Y- and Z-sustain power cables on Z-sustain. Power from TV disconnected for a couple of minutes before proceeding.

Check between VS and GND on 200 ohm range. Reading should start low then climb to overload (O.L or single "1".)

Repeat test for Y-sustain.

Replacement z-sustain board came in today, popped the new one in and tv is fully functional. Thank you tom.. you're the man, I couldn't have gotten my st working if it wasn't for you and the other posters. You all have happy holidays and God bless..

[tom66]

Re: LG 42pt350 A little help.

Enjoy your TV!

[drakar3]

Re: LG 42pt350 A little help.

I have the same symptons on the same exact tv which board in the pics are which

[Alastair E]

Re: LG 42pt350 A little help.

The board that connects to the long thin boards with lots of chips on running down the edge of the set is the Y-sus or Y-main board. It will also be marked what board is what.

[drakar3]

Re: LG 42pt350 A little help.

when i unplug i get continuous clicking from the power board

[drakar3]

Re: LG 42pt350 A little help.

what are the symptoms of a bad power board

[johnboy1313]

Re: LG 42pt350 A little help.

Drakar3, I just brought the same tv home. I'll try to get it opened up tomorrow night and see what I can find.

[chaplu]

Re: LG 42pt350 A little help.

Hello Guys
This is my first post in here. So hello to all of you. I have the same model LG pt350r that is having same symptom which is clicking sound and no turning on. When i unplug z board i can turn on tv without picture or sound but i can see that remote works and just like it used to turn on it does one relay click and then little humming of running tv. Any help would be appreciated.

Thanks

[ghost26]

Re: LG 42pt350 A little help.

Change the Z Sus Board man, that is the culprit.

[acbess]

Re: LG 42pt350 A little help.

This is also my 1st post here. I have the LG PDP50X30010 that has the same symptoms. The red LED would stay on and when the power button is pressed to turn on the tv, the green LED would come on, blink a few times, then a click, and the red LED will come on again. I have replaced 6 caps on the power supply board that were pop. I have tried all of the suggestions here short of replacing any of the boards. I did one other thing that has not been mentioned here and that is UN-plugging the connector on the power board that connects to the audio MAIN Board. The connector is labeled P802 on the power supply board. When I un=plugged this connector, the green LED stays on. Does this mean the Z_sustain board still is the culprit or does this mean that the main board need to be replaced. I'd like to make sure before I order the Z_sustain board. Any help is really appreciated.

Thank You,

Alex

[nice99]

Re: LG 42pt350 A little help.

Hey guys,

I am currently having some difficulty with my plasma TV.
First off, its a LG 42PT350 (same as the thread starter).
-A couple of days ago, I was watching TV when I heard this loud popping sound from my TV. Immediately after, my TV turned off.
-I tried turning the TV back on but it made another loud popping sound then turned off.
-After that, whenever i try to turn on my tv (note: my TV has the red light showing always when "off" as normal), I hear clicking sound, then the red light starts to fade. it stays off for maybe 7 seconds or so, then the TV makes a clicking sound and the red light turns on again.
-From this thread, I have tried disconnecting the Y-sus from the Z-sus (and z-sus from y-sus) but the symptoms are the same as above.
-However, when I disconnect the z-sus from the middle top board (i dont know what its called), the TV turns on, i get the static sound that normal TV makes, but no picture. the TV stays on.

-could this be a bad z-sus board? please help. thanks.

PS: the caps on all the boards look okay (no deformities).

THANKS!

[johnboy1313]

Re: LG 42pt350 A little help.

Hey guys,

I am currently having some difficulty with my plasma TV.
First off, its a LG 42PT350 (same as the thread starter).
-A couple of days ago, I was watching TV when I heard this loud popping sound from my TV. Immediately after, my TV turned off.
-I tried turning the TV back on but it made another loud popping sound then turned off.
-After that, whenever i try to turn on my tv (note: my TV has the red light showing always when "off" as normal), I hear clicking sound, then the red light starts to fade. it stays off for maybe 7 seconds or so, then the TV makes a clicking sound and the red light turns on again.
-From this thread, I have tried disconnecting the Y-sus from the Z-sus (and z-sus from y-sus) but the symptoms are the same as above.
-However, when I disconnect the z-sus from the middle top board (i dont know what its called), the TV turns on, i get the static sound that normal TV makes, but no picture. the TV stays on.

-could this be a bad z-sus board? please help. thanks.

PS: the caps on all the boards look okay (no deformities).

THANKS!

With the Y-SUS disconnected from the Z-SUS, the set will not power on, right? With the Z-SUS disconnected from the power supply, the set will power on? If the set powers on with the Z-SUS disconnected from the PSU, the you've likely found the culprit (the Z-SUS).

[nice99]

Re: LG 42pt350 A little help.

Perfect! Thanks for the quick reply. I will order a new z-sus and replace it and update on this thread. Where would you guys normally order it? ebay?
Thanks

[nice99]

Re: LG 42pt350 A little help.

Hey guys,

I am currently having some difficulty with my plasma TV.
First off, its a LG 42PT350 (same as the thread starter).
-A couple of days ago, I was watching TV when I heard this loud popping sound from my TV. Immediately after, my TV turned off.
-I tried turning the TV back on but it made another loud popping sound then turned off.
-After that, whenever i try to turn on my tv (note: my TV has the red light showing always when "off" as normal), I hear clicking sound, then the red light starts to fade. it stays off for maybe 7 seconds or so, then the TV makes a clicking sound and the red light turns on again.
-From this thread, I have tried disconnecting the Y-sus from the Z-sus (and z-sus from y-sus) but the symptoms are the same as above.
-However, when I disconnect the z-sus from the middle top board (i dont know what its called), the TV turns on, i get the static sound that normal TV makes, but no picture. the TV stays on.

-could this be a bad z-sus board? please help. thanks.

PS: the caps on all the boards look okay (no deformities).

THANKS!

Hi there, I must return to this thread because the above solution did not work.

I ordered both a zsus and ysus board for my TV and replaced it. Upon turning the TV on, it did not work and it still had the same symptoms (turns on, red light goes off for a couple of seconds, then TV turns off again).

Please help. I currently have a new ysus board in and have my old zsus board. I saw that my old ysus board had a blue thing blown out which was why I bought a ysus board to replace it. that didn't work at all. please and thanks.

[79vloy]

Re: LG 42pt350 A little help.

Dear Nice99..
I had same problem with you. I heard Popping and suddenly my TV goes off with repeating clicking sound.
I had open the back Cover. and I head humming sound from Z-sus Board.

I still try to figure out which component were fail.

Anyone had this experience with LG 42pt350 TV? any solution?

[johns1mj]

Re: LG 42pt350 A little help.

I have a 42pt350 I am trying to do component level replacement on. I have tested it through using the information above. I am up to the y-sus board being shorted. I am trying to locate the components that are shorted on the board. I have found two mosfits that were shorted but I know other items are shorted. The repair kit is 5 items. Also I know the y-buffer board has shorted ic's on it. I am going to replace that board.

Found this video on youtube- https://www.youtube.com/watch?v=4b2j1B7cOQY
Not the exact tv but a lot of good information.

[johns1mj]

Re: LG 42pt350 A little help.

Also found this
https://cdn.badcaps-static.com/pdfs/...02e604d94e.pdf
Going to try to see if I can follow it.

[akajester]

Re: LG 42pt350 A little help.

I have a 42pt350 I am trying to do component level replacement on. I have tested it through using the information above. I am up to the y-sus board being shorted. I am trying to locate the components that are shorted on the board. I have found two mosfits that were shorted but I know other items are shorted. The repair kit is 5 items. Also I know the y-buffer board has shorted ic's on it. I am going to replace that board.

Found this video on youtube- https://www.youtube.com/watch?v=4b2j1B7cOQY
Not the exact tv but a lot of good information.

Hello, I saw a repair kit in ebay that contains 4 items which is supposed to fix 90% of the issues with the zsus board. Do you think this would be worth trying vs buying a replacement board? Thanks.

[ddw75169]

Re: LG 42pt350 A little help.

Yes brilliant.

Unplug the TV.

Take a piece of wire and connect the two holes marked as red in the highlighted area on the pic

Unplug the LDVS cable (the one that goes from control board to the main board)

Turn the TV on.

You should see test patterns, do you?

OK, pardon me for being the luddite in the room but back in my vacuum tube days we didn't have film cable connectors. How exactly do I release this without damaging the film cable please?

[tvtimmy]

Re: LG 42pt350 A little help.

Use your fingernail and flip up the brown latch from the cable side.