Mode#47LG70 screen blanking LG LCD 47"

[cheapshot]

Good day all. The referenced TV will cut on fine but as soon as a video source is plugged to ANY HDMI port, the screen's backlight will cut out and then back on and will do this about 10 times then stop for a few seconds then start again. This is not a flashing or strobe effect like I have seen a lot on here addressed. Its like the backlight literally cuts out then back in every half second.

With no video input the TV stays on fine. Where should I start with this one?

[budm]

Re: Mode#47LG70 screen blanking LG LCD 47"

Does it do that using other Video ports?

[cheapshot]

Re: Mode#47LG70 screen blanking LG LCD 47"

Have not tried others but I can if needed? Wouldn't this point to power supply board if the inverters are powered from this board?

[budm]

Re: Mode#47LG70 screen blanking LG LCD 47"

Have not tried others but I can if needed? Wouldn't this point to power supply board if the inverters are powered from this board?

Power supply is unstable, or inverter board is unstable, or the BL-ON or DIMMING signal form the main board are not steady.
You have to take Voltage measurement at the least.

[cheapshot]

Re: Mode#47LG70 screen blanking LG LCD 47"

ok where should I test first? I can post back with what I see a bit later

[budm]

Re: Mode#47LG70 screen blanking LG LCD 47"

Why don't you try other Video ports first?

[Davi.p]

Re: Mode#47LG70 screen blanking LG LCD 47"

Hi, do you have made tests always with the same video source? Same hdmi cable? Tried with source inserted with the tv sw.on from cold?

[cheapshot]

Re: Mode#47LG70 screen blanking LG LCD 47"

ok will try other sources but from cold screen will blink if source is inserted