LG 50PV450 Plasma Color issue

[dhoff024]

I have a friend with a LG 50PV450 that is having some issues with the color. When the tv is on it will almost dim and lighten on its own it will go from regular to dark to darker and back to regular (energy saving sensor is off). It isnt super drastic but as it gets darker the skin tones get very red. I have worked on many lcd/led tvs and was able to fix them with the help of this forum but this is my first plasma so I am not sure where to start. I will post a picture of the board to help diagnose the problem.

[capkid]

Re: LG 50PV450 Plasma Color issue

It sounds like it could be a ZSus issue. You'll need to start by checking for the standard voltages - there should be labeled test points on each of the boards:

(1) PSU: VS and VA
(2) YSus: -Vy and VSCAN
(3) ZSus: VZB

[tom66]

Re: LG 50PV450 Plasma Color issue

Wow, the PV450 from LG seems to be a reliable model. A lot of these late model plasmas seem to be pretty crap for reliability. Ugh.

[capkid]

Re: LG 50PV450 Plasma Color issue

Wow, the PV450 from LG seems to be a reliable model. A lot of these late model plasmas seem to be pretty crap for reliability. Ugh.

Yeah, threads for these TVs seem to be popping up frequently. Disappointing.

[Shinju]

Re: LG 50PV450 Plasma Color issue

Check the solider joints on the copper inductor coils on both the y and x boards.

[dhoff024]

Re: LG 50PV450 Plasma Color issue

[dhoff024]

Re: LG 50PV450 Plasma Color issue

https://www.flickr.com/photos/98096475@N02/16185748993/

https://www.flickr.com/photos/98096475@N02/16598386077/

https://www.flickr.com/photos/98096475@N02/16618098318/

https://www.flickr.com/photos/98096475@N02/16805657585/

https://www.flickr.com/photos/98096475@N02/16804580312/

https://www.flickr.com/photos/98096475@N02/16805660995/

https://www.flickr.com/photos/98096475@N02/16805662445/

[dhoff024]

Re: LG 50PV450 Plasma Color issue

Sorry for the delay also I was having a heck of a time getting the pictures to upload and now I put links and got the images to upload go figure but this is what I am working with I dont know if anything looks out of order or not but if anyone sees anything let me know. Also how do I check the voltages as suggested above?

[tom66]

Re: LG 50PV450 Plasma Color issue

A common problem on these sets are cold solder joints on the various sustain board ERC inductors/coils.

The components in question are the two coils near the bottom of the Z-sustain board:
https://www.badcaps.net/forum/attach...4&d=1427480101

And the Y-sustain, between the black and silver heatsinks:
https://www.badcaps.net/forum/attach...3&d=1427480101

The solder joints on these often fail. Remove both boards and apply fresh solder to the joints (2 per inductor, 8 total)

[dhoff024]

Re: LG 50PV450 Plasma Color issue

A common problem on these sets are cold solder joints on the various sustain board ERC inductors/coils.

The components in question are the two coils near the bottom of the Z-sustain board:
https://www.badcaps.net/forum/attach...4&d=1427480101

And the Y-sustain, between the black and silver heatsinks:
https://www.badcaps.net/forum/attach...3&d=1427480101

The solder joints on these often fail. Remove both boards and apply fresh solder to the joints (2 per inductor, 8 total)

Just was able to take the boards off and take them home I desoldered the coils removed all the old solder and applied fresh solder to the coils I will test today and post the results. Thanks again for the help

[dhoff024]

Re: LG 50PV450 Plasma Color issue

Tv Has been up and running for a few hours now and seems to be fixed all colors look good and there is no fluctuation in screen brightness at all I would say that as of right now it seems to be fixed I appreciate all the responses I will update if anything changes.

[tom66]

Re: LG 50PV450 Plasma Color issue

Glad to hear - another one of these fixed.