LG 60PC1D-UE picture messed up

[tom66]

Re: LG 60PC1D-UE picture messed up

You wouldn't have any pic if your buffers were shorted.

[shelby5041]

Re: LG 60PC1D-UE picture messed up

i know...but per serv manual test method they are both shorted

i put 1 lead on large floating ground pad and raked pins where rubbon cables connect to.....

is this correct method to test for short?

[shelby5041]

Re: LG 60PC1D-UE picture messed up

i posted a pic of serv manual page couple messages back..can u verify my buffer testing method is correct?

[shelby5041]

Re: LG 60PC1D-UE picture messed up

and i havent tested tv for pucture recently....just been trying to isolate no vsc vsetup issue

it does appear buffers are shorted unless my method of testing is incorrect

[tom66]

Re: LG 60PC1D-UE picture messed up

Listen to me: Your buffers are not shorted if you have any picture.

You would not have a picture (that is, distinguishable lines, that show parts of an image) if your buffers were shorted.

If your buffers were shorted, your Vsc would be zero, not crazy.

[shelby5041]

Re: LG 60PC1D-UE picture messed up

ok testing method per serv manual is wrong

they prob made a typo



thanks

[shelby5041]

Re: LG 60PC1D-UE picture messed up

on my cheap multimeter vsc registers out of range on 1000v setting

does not fluctuate

sorry for all questions....just want to fix my tv

[tom66]

Re: LG 60PC1D-UE picture messed up

It's probably just the interference from the TV driving your meter crazy, you might need a better meter.

[mmartell]

Re: LG 60PC1D-UE picture messed up

Main board = a/v input board.

Run the test patterns !

[tom66]

Re: LG 60PC1D-UE picture messed up

Don't think you can on this one...

[shelby5041]

Re: LG 60PC1D-UE picture messed up

dont know how to run a test pattern.....and i used my neighbors fluke meter and get same results for vsc vsetup

[shelby5041]

Re: LG 60PC1D-UE picture messed up

tom....i believe serv manual wrong on testing buffers

i tested all 4buffers i have and same pins on all 4 had continuity......which i thought was odd....so i did more testing and it appears on each connector therr are 4ground pins ....so you cant rake all pins ..if u look on bottom of board trace compared to top of board you can see which pins are ground....so it appears buffers are not shorted as you stated.

sorry....

[shelby5041]

Re: LG 60PC1D-UE picture messed up

im going to buy another logic board and see how tv acts

you 100% do not think its a z or p/s issue?

and what about main a/v board like martli said could be?

[tom66]

Re: LG 60PC1D-UE picture messed up

I already said I didn't know what the fault was without using a scope on the TV to tell what is wrong with the drive waveforms. It's not the typical kind of fault you get with a Z-sustain failure.

[shelby5041]

Re: LG 60PC1D-UE picture messed up

ok thanks if another logic board doesnt fix it ill throw tv in trash

i appreciate ur help...it appears this tv may be non fixable for me

[tom66]

Re: LG 60PC1D-UE picture messed up

I'd put it up for FREE on Craiglist/etc or even ebay so it doesn't get completely trashed, if you can't fix it.

[shelby5041]

Re: LG 60PC1D-UE picture messed up

maybe.....

but sure does look like not fixable..we will see...maybe i will keep until someone has same issue and can tell me specifically what needs to be replaced

thanks

[shelby5041]

Re: LG 60PC1D-UE picture messed up

thats how i fixed my samsung 60 inch..it had a very common issue and i fixed it

[shelby5041]

Re: LG 60PC1D-UE picture messed up

hi just got 3rd control logic board

no change

same exact symptoms....i would say this confirms that it is not a control logic issue

if someone has any advice what could be causing the issue i would appreciate it

i have replaced buffers.....no change at all ..same no vsc no vsetup voltages
i have replaced y board..no change at all...same no vsc.. no vsetup voltages
i have replaced control board 2 times.no change at all..same no vsc and no vsetup voltages


only way i get good vsc and good vsetup is if power to control board is disconnected

and removing power to control board and getting good vsc and vsetup voltages happens with all the boards i replaced...in any order...doesnt matter

[shelby5041]

Re: LG 60PC1D-UE picture messed up

what else could cause missing vsc and vsetup voltages only when logic/control board power cable from y board is connected?

and when power to logic is disconnected from y board...vsc and vsetup voltages are good