LgTv 55lm860 thin horizontal lines equally spaced

[paulusone]

My lg has horizontal lines spaced apart about 6mm from top to bottom more dominate on right hand side, have disconnected tcon output left and right one at a time the left one removed gives a clean picture, the right output removed and the lines are there, suspect the panel or the thin wide pcb's at the bottom of the chassis cant seem to get the ribbons undone help would be appreciated for access to these.

[Andrew F. Ali]

Re: LgTv 55lm860 thin horizontal lines equally spaced

Clean and re-seat the LVDS cable from the Main Bd to the T-CON Bd and the two FFCs from the T-CON Bd to the Panel. This looks like the T-CON Bd is not producing the CPV1, 2 and 3 signals.

[paulusone]

Re: LgTv 55lm860 thin horizontal lines equally spaced

Thanks for reply help needed how to unlatch ribbons to lower panel pcb's close inspection shows witness marks of previous attempt, could it be the tcon as I assumed the tcon produces vertical error, see attached picture for ribbon cables other cables re seated no change, could try tcon in oven to reflow and will look at circuit to find cp1 etc

[Davi.p]

Re: LgTv 55lm860 thin horizontal lines equally spaced

I ask you to use commas and other symbols first..
Don't reflow tcon, it's a panel defect. I guess the tcon is on the bottom, check the model code of the panel, if no label present check the main tcon chip's brand. I guess the problem can be on the panel's board. To F.Ali: CPV are clock signals? How can them matters on this case? It stands for Clock Pulse Vertical? i'm away from home i can't check my notes...

A possible remedy: search for STVP testpoint on tcon, check with DMM to which of the pins on the connector versus the panel's faulty side it goes, then take adhesive tape , cut a thin stripe an place i to mask only that signal on the flat cable. Test tv.

[budwich]

Re: LgTv 55lm860 thin horizontal lines equally spaced

Thanks for reply help needed how to unlatch ribbons to lower panel pcb's close inspection shows witness marks of previous attempt, could it be the tcon as I assumed the tcon produces vertical error, see attached picture for ribbon cables other cables re seated no change, could try tcon in oven to reflow and will look at circuit to find cp1 etc

you are likely on the right track about the cable clamp at the bottom. The clamp mechanism is the same as the other ones that you disconnected at the tcon... the "clamp" lifts up.... try using a credit card as a "lever" across the whole clamp "lever". Since you get a good picture with the one side disconnected, it is likely the cable and / or clamp on the other side that has an issue... could be even as simple as a misalignment and might be the reason that you are having such a hard time unclamping the connector.

[Andrew F. Ali]

Re: LgTv 55lm860 thin horizontal lines equally spaced

i ask you to use commas and other symbols first..
Don't reflow tcon, it's a panel defect. I guess the tcon is on the bottom, check the model code of the panel, if no label present check the main tcon chip's brand. I guess the problem can be on the panel's board. To f.ali: Cpv are clock signals? How can them matters on this case? It stands for clock pulse vertical? I'm away from home i can't check my notes...

A possible remedy: Search for stvp testpoint on tcon, check with dmm to which of the pins on the connector versus the panel's faulty side it goes, then take adhesive tape , cut a thin stripe an place i to mask only that signal on the flat cable. Test tv.

+100