Hi initially suspected Va & Vs being low but they do come back up to very near spec.
The screen looks pixelated & blotchy any ideas?
The screen looks pixelated & blotchy any ideas?
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Re: LG 42PJ350 panel death ?
check z-sus for shorted transistors and open resistors. -
Re: LG 42PJ350 panel death ?
Well it was R279 a 2.2 ohm resistor dead no connection
Resoldered the 2 large coils & igbts etc for good measure.
Good picture restored.Comment
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Re: LG 42PJ350 panel death ?
Great job! Very useful information.Comment
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49UJ6500 LCD panel has a lighter band on top when first powered on. Goes away (or gets much fainter) after TV on for a few min. After powered off for awhile and power back on, same band appears. If powered on immediately after powering off, no or much fainter band. Running the latest firmware.
Disassembled the TV and lifted the LCD panel during testing. Band is on the LCD panel (can see the band on the panel as I lift it slightly) Backlight is perfectly even at the top edge. Double checked LCD panel alignment in the frame and is perfect but since band moved with the panel, its on... -
TV flashes backlight then reboots over and over. no image. Client said it used to have image for a bit before rebooting. Got worse over time.
tcon is built into mainboard.
Only one cable goes to panel boards.
there is a cable from one panel board to the other that links them.
cost cutting measure that results in us having harder time to diagnose.
removing the link to the second panel board allows TV to stay on with stable backlight but no image.
used cut off tape method to mask 1 maybe 2 pins on the side of the cable that goes to that second panel board.... -
I had a the above tv qn55q60r that had a bad panel but everything else good. I had another panel here from un55nu6900 with bad leds and melted diffusers.
I put the nu6900 panel in and powered it up and it does work but there are lines vertical lines.
I was trying to change the panel type in the service menu but don’t see my exact panel. Anyway to fix this or someone have similar experience.
the clear picture is the panel type from the service menus on the nu6900. The other 1 is the panel type that was set for the q60r with the bad panel....01-13-2024, 01:57 PM -
I have a TCL 55P6US with sound and backlight but no picture. This model does not have a T-CON board, and the right (rear perspective) panel board is fed from the left panel board. I have not been able to induce any change by disconnecting the secondary panel board or the tape cut-off method on the primary board.
There are a bunch of voltages missing on the panel boards. I can't find any shorted caps of the panel boards, and all of the missing voltage rails read in the kiloohms, which leads me to suspect the issue may lie on the circuit board, rather than a short in the panel.
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I came across a 50inch TU8000 that wouldnt start up properly (blinking stand-by light, backlights would cycle on and off).
When i opened it up and removed the power to the mainboard the backlights powered up and everything looked uniform.
When reconnected the mainboard but disconnected the flex cable to the panel i heard the TV startup with the intro sound.
Later I checked for shorts on the panel PCB boards but could not find anything.
When I took a look with the FLIR i noticed the 2 resistors...08-10-2024, 08:39 AM
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