Lg 60ps60-ua

[Crawl71]

Hey Guys,

So before I start I just thought I would say sorry in advance as I know some of you may have answered this many, many times! I did do a forum search but only had 5 hits on my specific tv and none really helped out.

I have the noted LG 60" tv. It worked fine and then one day the picture went, with sound, turned it off and back on and the picture and sound were gone. Now, when I turn it on, I get a slight bit of brightness and sometimes a flash of the channel in the top corner but otherwise nothing. So here is what I have done so far...

- tested all voltages on main board, power in and out on ZSUS/YSUS boards
- removed and tested both upper and lower buffer boards with no found problems
- all capacitors seem to be okay by sight; although I don't have an esr meter to test in-line.
- uplugged both zsus and ysus one at a time to test for sound; nothing.

I did read another post in which the user was directed to do a test pattern to see if it was the main control board...however, that was a different unit and my board obviously is not the same and I am not sure where/what to jump to get the test pattern.

Any other assistance, suggestions would be greatly appreciated. I don't mind replacing a board but I don't want to start spending hundreds of dollars on this TV.

Thanks!!

[Crawl71]

Re: Lg 60ps60-ua

Just wanted to pop back on and give a slight update.

I did find a troubleshooting schematic and it said that I need to jump pin 1&2 on the 'Auto-Gen' (P6) while having removed cable LVDS. I did try this but I had to assume what pin 1&2 were; was not able to produce the test pattern. Should I be using R52 & R53 instead?

[Hamie]

Re: Lg 60ps60-ua

pin 1 has the little triangle above it.

what are the run voltages?
VS
VA
VSC
-VY
VZB

the test points are shown on the manual you've uploaded

[Crawl71]

Re: Lg 60ps60-ua

Hi Hamie,

Okay, I am by no means an electronics guru so hopefully I touch on all the points you were asking for or got the right ones...I've included probably more than you asked for!

Main Board
VS - 194.2 (1/2)
VA - 67.2 (5/6)
M5V - 5.06 (8/9)

ZSUS
+VS - 194.2
+5V - 5.06
VZB - 67.2

YSUS
VS - 194.2
VA+ - 67.2
+5V - 5.04
-VY - 15.27
VSC - 15.83

Control Panel
M5V - 5.06

Also of note, I did try and get a test patter without success and if it means anything, D7 is solid green and D6 flashes green.

[Crawl71]

Re: Lg 60ps60-ua

Just a quick update....

YSUS
-vy = 9.62
Vsc = 10.72

Still have not been able to successfully complete a pattern test. Would this push me more toward the YSUS board being the problem?

[augiedoggy]

Re: Lg 60ps60-ua

Hey Guys,

So before I start I just thought I would say sorry in advance as I know some of you may have answered this many, many times! I did do a forum search but only had 5 hits on my specific tv and none really helped out.

I have the noted LG 60" tv. It worked fine and then one day the picture went, with sound, turned it off and back on and the picture and sound were gone. Now, when I turn it on, I get a slight bit of brightness and sometimes a flash of the channel in the top corner but otherwise nothing. So here is what I have done so far...

- tested all voltages on main board, power in and out on ZSUS/YSUS boards
- removed and tested both upper and lower buffer boards with no found problems
- all capacitors seem to be okay by sight; although I don't have an esr meter to test in-line.
- uplugged both zsus and ysus one at a time to test for sound; nothing.

I did read another post in which the user was directed to do a test pattern to see if it was the main control board...however, that was a different unit and my board obviously is not the same and I am not sure where/what to jump to get the test pattern.

Any other assistance, suggestions would be greatly appreciated. I don't mind replacing a board but I don't want to start spending hundreds of dollars on this TV.

Thanks!!

I had the same problem with the same tv 6 months ago... take a heatgun to the main board and youll find it will likely start working again but it may not last.. one of the chips on the board is failing and I never did track down which one. (actually I reflowed all the solder joints on the board and the sets been working since.)

[augiedoggy]

Re: Lg 60ps60-ua

I should add I had just a glowing black screen I believe due to the cost of the board that the main board is usually the issue with this set. You might want to do a search because I got the recommendation for the heat from another thread here on this set when doing a google search.

[Crawl71]

Re: Lg 60ps60-ua

Okay. Back to the drawing board.

- unsuccessful at reflow; might try again

I have noticed that I get a bit of hiss out of the speakers which I didn't notice before.

Have still not been able to get a test pattern.

Did a test on the logic board according to the instructions posted and was okay.

Not sure where or what else to try. I'm sure I'm missing something!

[Hamie]

Re: Lg 60ps60-ua

OK first a few things.

Don't listen to augiedoggies post, I have no idea why they would think reflowing a mainboard would fix a plasma that clearly has a fault with the y-sustain.

You're lucky it doesn't appear to have damaged the board.

Your vsc and -vy voltages are far too low.

Vsc sound be around 150v
-Vy should be around -180

Unplug both the buffers and see if vsc and -vy come up.

[Crawl71]

Re: Lg 60ps60-ua

First off, thank you for the suggestion.

The test you suggested did not return the results that I would have suspected according to your reply.

Buffers connected
VSC - 10.6
-VY - 11.75

Buffers disconnected
VSC - .006
-VY - 1.26

[kca]

Re: Lg 60ps60-ua

Hey guys ~

I have a similar issue, and am just jumping in here to see if I can learn/contribute in any way. Hoping Hamie has the next step of advice for you in the troubleshooting process, Crawl71.

Would seem to me that if you are getting VS @ around 200 and Va @ around 60 coming into the YSUS, then your issue is most likely isolated on the YSUS board itself b/c of the very low readings when you have both buffers disconnected.

[Crawl71]

Re: Lg 60ps60-ua

Just to update, I have decided to take the plunge (based on these findings) and order a new YSUS board. It was difficult to find for this TV as everyone seemed to have been sold out. I will update again once I have received it and given it a try. Fingers crossed!

[kca]

Re: Lg 60ps60-ua

Thanks, Crawl ~

It will be interesting to know what happens with your new YSUS. It might become an option for me to consider too based on your results. If you want to follow my thread for potential insights, you can find it at:

https://www.badcaps.net/forum/showthread.php?t=61707

[Nick's Tvs]

Re: Lg 60ps60-ua

The main board will sometimes develop cracked solder joints between the BGA chip and the board itself which can cause picture problems. The heating portion with hot air can make it temporarily work again but I would advise against it as you could ruin your board and best case scenario only make it work for an additional few weeks to a few months. A new BGA chip or re-ball should be performed in order to have a successful repair. However as mentioned prior, the voltages on the sustain board seem weird. What really should be done is disconnecting the main board out of circuit and with every other board in circuit perform the color pattern test by shorting the auto exgene on the logic board. If the pattern test appears, then you know for sure bad main board.

[Crawl71]

Re: Lg 60ps60-ua

Just wanted to take a moment and thank everyone for all the help and direction. YSUS board finally showed up, installed and working like a charm again!! $120cad and my time. Can't beat that.