First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

[johnboy1313]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.



Here's the control board. I think it's been worked on too.

[johnboy1313]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

Sorry it's taken so long. My interest in fixing this has dropped off a bit lately.

[tom66]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

That looks like a factory mod to me.
Top right pin might be the clock.

[johnboy1313]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

Back to this one. I've had a few sets on the bench this past week that kept me from parting this one out. I'm still not ready to say the panel is bad. The evidence just doesn't support it. I worked on a Panasonic plasma this week and if anything the buzz emitted from the LG is quieter than the buzz emitted from the working Panasonic panel. I will attempt to get the scope again tonight.

That looks like a factory mod to me.
Top right pin might be the clock.

I assume you are saying I should scope the top right pin. Is this correct? Is this board also called the digital board? In this link, posts 11 and 13, a member going by the name randtek outlines a procedure for testing the digital board.

[tom66]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

You could call this the digital board. It is essentially the same as a T-con in an LCD TV.

Try scoping that top right pin.

[johnboy1313]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

From the top right pin. I can't think of anything else but the panel.

[tom66]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

Can't see a problem. I would expect the panel to glow with everything it is given...

[johnboy1313]

Re: First plasma, LG 42PC5D. Sound but no picture. Help me make sense of this.

Can't see a problem. I would expect the panel to glow with everything it is given...

I wish I knew more about this. Everything I've read says that the output from the boards should have looked odd, due to overworking, if the panel was bad. These boards do not appear to do that.

I've got that Panasonic plasma that I've posted about in another thread. Even when that set would not power on, I could clearly see the panel prime, even in a lighted room. This set does not do anything like that.

I just don't get it.