Lg49uj6200ua

[ljintexas]

Re: Lg49uj6200ua

I have never heard of Skyworth. I take it that it is a lesser quality set?

[ljintexas]

Re: Lg49uj6200ua

Standby voltage on the main PFC Caps is 162.5 Volts.

[ljintexas]

Re: Lg49uj6200ua

Here are pics of both sides of smps.

Thanks

LJ

[ljintexas]

Re: Lg49uj6200ua

Better picture of back

[ljintexas]

Re: Lg49uj6200ua Better Picture of back of SMPS

I am sorry for the poor quality picture..I think this one is much easier on the eyes.

[budm]

Re: Lg49uj6200ua

"Two main boards exhibit same behavior. A third main board would sometimes go into menu and even display PIP video and sound in menu on input selection screen. When input selected (HDMI) only audio came through, no display on full screen, this board took software update."
It looks like you do have main board problem, especially not all of them acting the same way.


"LED Outputs are both 64.75 steady instead of 66 volts." BL-ON is OK otherwise you will not get the LED Voltage.
BTW, on the LED connector, what are the Voltages on each one of the pin with ref. to GND? The 64.5V is ref. to GND?

[nomoresonys]

Re: Lg49uj6200ua

So if I read it right, you never get a good inverter on signal?

[ljintexas]

Re: Lg49uj6200ua

"LED Outputs are both 64.75 steady instead of 66 volts." BL-ON is OK otherwise you will not get the LED Voltage.
BTW, on the LED connector, what are the Voltages on each one of the pin with ref. to GND? The 64.5V is ref. to GND?
__________________
Yes Sir Bud. 64.75V to chassis. I can check them to the corresponding GND terminal on the same connector. Will do so and post.
INVON is 1.84V and I do get backlight.

So far both mains supposedly came from sets damaged in shipping yet they claim they are tested good. If they power up a set with a cracked panel, can it damage the main board?
My source for main board CPU replacement says no parts are available to repair the original main board.
Thanks to all for your assistance!! I appreciate it!


LJ

[nomoresonys]

Re: Lg49uj6200ua

Did you try this: To reset settings, press and hold down the OK button on the TV panel for 10 seconds.

[nomoresonys]

Re: Lg49uj6200ua

Another thing to try, with tv powered on unplug power cord from wall, wait 1 minute plug back in.

[nomoresonys]

Re: Lg49uj6200ua

What is hooked up to tv? when I test I just use an antenna, sometimes a bad cable box can cause problems.

[nomoresonys]

Re: Lg49uj6200ua

HOLD DOWN the power button on tv and while the lights are flashing, start pushing the menu button on the TV at the SAME TIME.

[ljintexas]

Re: Lg49uj6200ua

I will try that Nomoresonys!!

[nomoresonys]

Re: Lg49uj6200ua

A mysterious issue for sure.

[nomoresonys]

Re: Lg49uj6200ua

Was just reading a case where the tcon was the issue on a tv that shut off shortly after turning on.

[ljintexas]

Re: Lg49uj6200ua

If it were the tcon, I would not get LG splash screen and setup menu for language and time zone.

[ljintexas]

Re: Lg49uj6200ua

In answer to your question Bud, if I test LED+ to LED- I get 63.95 volts. If I check LED+ to PFC Main Cap -, I get 112 volts.
I am convinced that the CPU on this main board has only base rudimentary firmware on it or has a physical problem.. If I plug a USB drive into it, it will read the drive, but will not ask me if I want to update. If I boot cold with USB drive in, it will read it, but still not ask me if I want to update.

[budm]

Re: Lg49uj6200ua

"In answer to your question Bud, if I test LED+ to LED- I get 63.95 volts. If I check LED+ to PFC Main Cap -, I get 112 volts."
When testing the LED connector Voltgaes you will test the LED connector pins against cold/chassis GND.

[ljintexas]

Re: Lg49uj6200ua

Then 64.75 V is the answer.

Thanks!

LJ

[budm]

Re: Lg49uj6200ua

At this point you need to get known working main board.