LG 42PC1D Fuzzy Picture

[evs87]

Hey Guys,

I have been given this plasma for free so thought I would have a go at repairing it. It had sound but no picture. I traced it down to the IPM and a blown fuse on the YSUS. I have replaced both and now have picture but it seems to have a fuzzy look to it. The power board has a few swollen caps, could this be the causing the problem? I have added some pics for you to have a look at.

[tom66]

Re: LG 42PC1D Fuzzy Picture

Those definitely need replacement, they could cause the issue but I think it's more likely you have the common LG sparklies problem which is very difficult to fix, the panel has aged and the control board needs to have a firmware update.

You can try knocking Vs and Va down by about 5-10V and see if that fixes it; if not, tweak SET_UP and SET_DN on the Y-sustain.

[evs87]

Re: LG 42PC1D Fuzzy Picture

I have already adjusted the SET_UP / DOWN to get rid of the "red snow" which worked for the redness but not the sparkles.

How would I Know when I have adjusted it by 5-10V? Sorry if it's a simple question, this is a little hobby I thought it have a go at!

[tom66]

Re: LG 42PC1D Fuzzy Picture

You would need to measure it with a voltmeter on the connector going to the sustain board. Nominally about 190V for Vs, 65V for Va for LG panels.

[evs87]

Re: LG 42PC1D Fuzzy Picture

OK great I'll give that a try. Would you do it before replacing the caps?

[tom66]

Re: LG 42PC1D Fuzzy Picture

I would recommend replacing the caps asap as the TV will start having problems powering up. It should work for now though.

[evs87]

Re: LG 42PC1D Fuzzy Picture

Cheers Tom, I'll have a go at adjusting the Vs / Va and if that works I'll replace the caps if not I guess down the dump it goes!