LG 60PZ550 plasma - no picture or sound ...

[sanstv]

Hi,
Tv quit working while paused for a few minutes. Came back and no picture (sound was through home theater and working fine).

Checked via tom66's troubleshooting steps: checked with zsus and ysus disconnected separately; also checked the following voltages: va 55, vs 202, vzb 110, vy -178, vsc 148, zbias 0, vzb1 2, and vzb2 0. Also jumpered r51 and r52 and disconnected main board ribbon cable which got test pattern (first sign of life). I am hopeful but not sure where to go next. Thank you for any help you can provide.

[tom66]

Re: LG 60PZ550 plasma - no picture or sound ...

Your tests indicate the main board is bad, this is a very common fault on this model and LG plasmas in general.

You can use 50PZ550 main board. You cannot use any 42" main board or 50"/60" 720p main board from same generation.

[sanstv]

Re: LG 60PZ550 plasma - no picture or sound ...

Tom, thank you for the info ... it appears that the main board is out of stock most places. Is a replacement necessary or is there a test for a particular part that can be done? I really only require one HDMI port but two would be ideal. I could live without the other ports/connections.

[sanstv]

Re: LG 60PZ550 plasma - no picture or sound ...

i havent found a repair kit yet but if anyone knows a source please let me know.

[tom66]

Re: LG 60PZ550 plasma - no picture or sound ...

I wish we could find the fault with these main boards. I suspect the majority of them are firmware corruption due to bad NAND/NOR flash or software bugs.

[fishyengineer]

Re: LG 60PZ550 plasma - no picture or sound ...

I have a similar issue with the same model number. replaced the ZSUS and YSUS boards. Now, it powers up with a click, the ZSUS board buzzes for roughly 3-5 seconds, and another click where is powers off. If I power on again with the remote, same thing happens.

Already $140 in and feeling pot committed. Help!!!!

[tom66]

Re: LG 60PZ550 plasma - no picture or sound ...

I have a similar issue with the same model number. replaced the ZSUS and YSUS boards. Now, it powers up with a click, the ZSUS board buzzes for roughly 3-5 seconds, and another click where is powers off. If I power on again with the remote, same thing happens.

Already $140 in and feeling pot committed. Help!!!!

Did you try the test pattern jumper? Best to create a new thread for your issue.

[fishyengineer]

Re: LG 60PZ550 plasma - no picture or sound ...

New to the process and can't figure out the posting process. I might not have access yet. I will search test pattern jumper.
I have quite a few people who do not believe I will be able to figure this TV out so I am extra motivated.

Thank you for responding.

[KrazyKman]

Re: LG 60PZ550 plasma - no picture or sound ...

I have similar issues. The LG 60PZ is such a dud, I wish there was more info about finding replacement parts and DIY guides.

[Lg60pz550]

Re: LG 60PZ550 plasma - no picture or sound ...

I have a similar issue with the same model number. replaced the ZSUS and YSUS boards. Now, it powers up with a click, the ZSUS board buzzes for roughly 3-5 seconds, and another click where is powers off. If I power on again with the remote, same thing happens.

Already $140 in and feeling pot committed. Help!!!!

Hello Fishyengineer,

I have an LG60PZ550 (same as your TV, and same problems); no picture with a click when turn on, with sound and a weak white glow on the screen.
So far I replaced the power supply board , but didn't fix the issues.
I about to purchase the Y, then Z board to replace but saw you have done that
with no results. Please confirm that you have replaced the y and Z sustain boards but that didn't fix the problems. I purchased the logic board and will replace it in and see if that will fix anything. I will let you know. Thanks

[tom66]

Re: LG 60PZ550 plasma - no picture or sound ...

Did you try the test pattern jumper?

[KevinCro]

Re: LG 60PZ550 plasma - no picture or sound ...

I have a similar issue with the same model number. replaced the ZSUS and YSUS boards. Now, it powers up with a click, the ZSUS board buzzes for roughly 3-5 seconds, and another click where is powers off. If I power on again with the remote, same thing happens.

Already $140 in and feeling pot committed. Help!!!!

The clicking noise is the relay on the power supply shutting down the system because a fault is detected. Are any of the ICs burnt on the y buffers? Is the zsus powered through the Ysus board? Use a multimeter set on continuity and see if any of the transistor's are shorted on your sustain boards. If so you can replace those it's not easy but it's much cheaper than a new board.

[maiden790]

Re: LG 60PZ550 plasma - no picture or sound ...

I wish we could find the fault with these main boards. I suspect the majority of them are firmware corruption due to bad NAND/NOR flash or software bugs.

I cracked the code! Thinking back to this one lg main board I fixed, I wanted to see if the same trick would work and it indeed did!

Step 1: Set your oven to 350 degrees Fahrenheit

Step 2: Place the main board in the middle of a cookie tray

Step 3: After your oven Preheats to 350, place the tray with the main board in the oven for 10 minutes!

Step 4: Take it out of the oven after 10 minutes *IT WILL BE HOT BUT NOT MELTED*, and place on top of the stove to cool down for an additional 20 minutes.

Step 5: After the board is cool to the touch, put it back into the tv and Waalaa its fixed

Ive fixed one of my other tv's this way and im not sure why but it works. I think its something with the heatsink. Xbox360's have the same issues

Trust this method! after all what do you have to loose!?
** make sure that your main board is definitely faulty buy doing the jumper trick!**

[Hogeagle]

Re: LG 60PZ550 plasma - no picture or sound ...

I have LG 60PZ550 PLASMA TV. The first the problem was no picture on screen but only audio. I opened the back panel and found the ZSUS with fuse blowed out and coils sink welding ckacked. I changed the fuse and welded back the coils on board. Now I turn the tv ON and quickly it turns back OFF. I disconnected the ZSUS board and plugged power back ON, on but no picture, also I noticed buzzing noise from ZSUS board. I removed the ribbon cable from CTRL to YSUS board and noise stopped. I also did the test with the jumper on R51 and R52 I got the colors on the screen but also are big black spots on screen. I removed the jumper and put everything together except the ZSUS board connector, I have 20% of picture I mean poor quality with black spots. My question is which boards I need to replace to make this tv good again. Please any advise?

[minionan]

Re: LG 60PZ550 plasma - no picture or sound ...

Your problem seems to be same as mine; faulty Z-sus board. Check two last posts under the thread "LG 60PZ550 Plasma - No Sound, No Picture" (https://www.badcaps.net/forum/showth...262#post664262) to see how I managed to repair the TV.

Check all MOSFET's and IGBT's on board, order the faulty components and change them. Good luck!