LG 50PC55 Plasma Vertical Bars!

[studfish]

Hi I have an LG 50PC55 plasma which has some wide colour bands which move side to side on the screen.

I have replaced both y-buffer boards as they were faulty but it is still the same!

Also when switched on the red standby light goes off but there's no green light coming on.... it also switches itself off after about 10 seconds.

Any help would be appreciated
Thanks

[tom66]

Re: LG 50PC55 Plasma Vertical Bars!

You got bad y-buffers then.

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

Those vertical bars are the "No Signal" box. The horizontal black bars suggest that you may need to reseat a ribbon as well.

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

Hi thanks for the replies..... sorry for the noob questions but im new to this.

I assume the "No Signal" box means I have no Arial dvd etc connected?

Those bars still appear when i have Arial dvd etc connected.

Any ideas why the green light wont come on?

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

just as an update i have disconnected power from the zsus board and the tv no longer powers off after 20 seconds could the zsus be the problem ?

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

Hi thanks for the replies..... sorry for the noob questions but im new to this.

I assume the "No Signal" box means I have no Arial dvd etc connected?

Yes and no, you could have them connected but not selected, like if your DVD was connected to HDMI 1 but your TV was set to A/V 1. The TV would still not see a signal.

Those bars still appear when i have Arial dvd etc connected.

If you're playing a DVD and you can hear the movie's sound, then I am mistaken. Though, if you look at the picture, I'm still thinking the first thin solid white vertical bar is the word "No" spread up and down on the screen. The second, thicker, solid white vertical bar is the word "Signal" spread up and down on the screen. The No Signal box moves to random places on the screen to prevent burn in. As the box moves, it makes sense that the bar would move with it.

Any ideas why the green light wont come on?

You could be looking at a sustain problem. Try unplugging the Y-Sustain on the left side and powering the TV on? There will be no picture obviously, but if the sustain board is faulty, you should see your green power on LED.

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

There is no sound coming from the tv either even with devices connected to it..

I have had both the ysus and xsus disconnected and still no green light

I have no remote for the tv either and if i use the buttons along the bottom the tv turns off

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

I didn't see it earlier but you say that the set powered on and didn't shut off with z-sus disconnected. I would focus on the z-sus. Has this always been your tv or did you buy it to repair it?

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

I have just bought it to try and repair it

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

Are you sure the LED is supposed to turn green?

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

I've just been looking at an online manual and it states the light should turn green?

I removed the z-sus and re-soldered the joints checked fuses etc. the tv now does not turn itself off however no matter what i try to connect to it.....hdmi rgb scart antenna it doesn't seem to be able to get a signal from any of them?

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

When you change inputs, does the screen flicker? Do any other bars appear on the screen? Can you tell that the input is actually changing?

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

when changing input the bar on the screen appears in the center of the screen for a few seconds...goes of then starts moving around as tho theres no signal

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

I'm not 100% familiar with this set. Are you using the remote or the TV to select inputs? The reason I ask is because on some TVs, if you push the input button on the TV, you have to use the channel button to switch between inputs. If you're using the remote, I would think it just changes to the next available input.

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

I'm using the tv controls as i have no remote.

I've just tried both ways and its still the same

Also if i press the menu button on the tv.....the tv turns off

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

Unfortunately, I'm unable to help. Hopefully, someone with more knowledge can step in.

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

Thanks Johnboy I really appreciate you help so far.......It wont beat me that I do know

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

No problem.

[johnboy1313]

Re: LG 50PC55 Plasma Vertical Bars!

You got bad y-buffers then.

Have you tested the new buffers? Tom has a good point. He knows more about these than I probably ever will. It is extremely possible to buy parts that don't work. Sellers advertise that the parts were pulled from sets with broken screens, but how do they know that the screens weren't broken out of frustration because the TV wouldn't power on or show a good picture?

[studfish]

Re: LG 50PC55 Plasma Vertical Bars!

Hi I have tested the new buffers and the top buffer is showing as having a blown ic.

Would this cause the no signal problem though ?