Complaint was no display, confirmed and I saw
this series USA model is very prone to backlight failure, so
ordered (8) new strips. Opened up the TV, and am testing the old ones. So
far all the ones on the right side are lighting up ok,
the set of strips connected to them via the connector side with the plugs
are not lighting up at all, even when I supply power directly
to the pins on that side.
I took out a set of the new strips, connected them together and tested, and
they are doing the same thing...whats going on? Thought these were all in
parallel.
If I separate the strips, the one with the connector plug seems to not
light. I have not gone through all the
new ones yet to test. I suppose they could be defective but strange how all
the ones in the TV on that side are not lighting and the others are.
Anyone have an idea whats going on here? 
hello!
Disconeected the main board from power supply. In case the baclight supply working continosualy. Some led strip switcing in parealell, if one tsrip the led opening voltages little bit higher the another then the backlight controller will be off. Some time the baclight controller is bad.
Laszlo
2
Hi,
Original issue I thought was no backlighting, so I looked at the strips. They test ok...and when I look at the tv with the lights off, there is a backlight, so thats ok. No picture or OSD
is the real issue so I changed the main , then the TCON, no difference. If I disconnect half the tcon cable from the panel, I get one side that looks like good picture. This is with either TCON, old or new. The other side when disconnected shows a all white raster on that half of the screen, I'm told that means bad panel.....?
Other tech says look at the buffer pcb between the TCON cables and the panel, check for corrosion due to Windex leaking in the front cover through into the pcb. I have not opened that part up completely, but I shined a flashlight in to see and theres no corrosion that I can see. I guess I should look at that entire board 100% close but so far I am told this is usually a bad panel.
1
Turns out this was normal for the LED's, I think they are in series is the reason, so the strips were ok. After changing the main pcb, then the TCOC, it was concluded the panel was bad.
1