LG Plasma 42V8&X3

[ViperRunner]

Hi,

Some time ago, this plasma started having difficult starts, until the point when it had to take a new YMain YSUS.

This resolved the problem for around 2 or 3 months, but from this point on, the screen had a bit of white grain on the right corners but was sustainable.

some days ago, it failed completely again.. now it's always trying to start, i can ear the relay clicking on and off and see the red led blinking, but it never gets to start. if i disconnect the XSUS and YSUS from the PSU it keeps doing the same. I think it's not the PSU board.. Does someone make any idea of what it may be?

I'm also leaving here the service manual for this set, for anyone who needs it.

Thanks for looking!

Best regards

[Alastair E]

Re: LG Plasma 42V8&X3

Have you checked for any shorts on the Vs lines of the X-SUS/Y-SUS boards?
--As you probably know--IPM's are a prime suspect on these sets....

There is a fault that causes the PSU to do strange things. Its something to do with the opto-couplers and can be sorta cured by shorting two of them out--some guys have tried finding the actual fault this dodge covers up and spent quite some time doing so--but it hasn't been discovered just what causes it, but its believed to be on the PSU board.

There's a thread around here somewhere about this fault, I'll see if I can find it....

[ViperRunner]

Re: LG Plasma 42V8&X3

Have you checked for any shorts on the Vs lines of the X-SUS/Y-SUS boards?
--As you probably know--IPM's are a prime suspect on these sets....

There is a fault that causes the PSU to do strange things. Its something to do with the opto-couplers and can be sorta cured by shorting two of them out--some guys have tried finding the actual fault this dodge covers up and spent quite some time doing so--but it hasn't been discovered just what causes it, but its believed to be on the PSU board.

There's a thread around here somewhere about this fault, I'll see if I can find it....

Thanks for the quick reply Alastair.

But i already disconnected both the YSUS and XSUS, so if one of them was the issue, the rest of the circuit should start up right?

regards

[selldoor]

Re: LG Plasma 42V8&X3

Here is Tom66's fault guide for plasma - may be of help.
https://www.badcaps.net/forum/showthread.php?t=18542&

[tom66]

Re: LG Plasma 42V8&X3

That guide is in serious need of an update. A common (ish) fault on these is AC detect failure. Yet checking the AC det voltage on PSU connector going off to main board.