LG 47LN578V left hand column of screen flickering darker at regular rate

[RobbieC]

My LG 47LN578V developed an annoying 'feature' yesterday.
An approximate 30cm (1 foot) column on the left of the screen consistently darkens, then returns to the same level as the rest of the screen at a rate of just under 0.5 Hz.

The picture quality of fine just the light level.

This is the set which had a full led backlight replacement done at Xmas and knowing how the circuit works it obviously isnt that!

Thoughts ?

[Diah]

Re: LG 47LN578V left hand column of screen flickering darker at regular rate

My LG 47LN578V.....The picture quality of fine just the light level.

the fine picture are at exact the middle of the screen ?

[RobbieC]

Re: LG 47LN578V left hand column of screen flickering darker at regular rate

Http://1023.co.uk/MOV_0268.mp4
Http://1023.co.uk/MOV_0269.mp4
Video not great but you can see the effect

[Diah]

Re: LG 47LN578V left hand column of screen flickering darker at regular rate

okay i can see its not exact at the half of the screen, you have one line of backlight dim play the effect, need power board close photo. so other like budm and other good users can following with.

[RobbieC]

Re: LG 47LN578V left hand column of screen flickering darker at regular rate

It appears to be the left 1/4 of the screen but the whole column from top to bottom.
Do you mean the led back light as it cant be that due to it running horizontally and in 2 strings which would mean the whole string would dim which would be visibile accross the whole of the screen.

[Diah]

Re: LG 47LN578V left hand column of screen flickering darker at regular rate

It appears to be the left 1/4 of the screen but the whole column from top to bottom.
Do you mean the led back light as it cant be that due to it running horizontally and in 2 strings which would mean the whole string would dim which would be visibile accross the whole of the screen.

as i know the 2 LED strips are at the bottom of the Panel, each Strips had 4 groups they are separated by dimming. this what i know on 47 of LG LN series, if yours are 2 strips only at behind the Panel, then you have right.. however to be sure 100% please disable the ECO at setting, Auto Contrast OFF, and the backlight put it on level of 50. and watch if this issue happen again.

other wise its need too to resitting LVDS and Ribbon cable as those could be the issue too.