There is audio, but no picture. White flash when power up. No visible signs of light emitting from inside when room is dark. Menu is visible with flashlight on screen. Three PCB's on chassis. One PCB has external input jacks, one PCB is labeled high voltage supply, and last PCB has two ribbon cables attached to the screen.
The video circuit is compromised and perhaps the circuit board was damaged. This can happen via power surge or age of the devices. With proper test equipment the video circuit can be traced to find the problem.
SOURCE: JV50P has power but that's about all
if Vs is showing less than 1 ohm, that is your shorted line. it goes the sustain and address boards (big boards on left and right side of set) and one of those is bad. try using the same ohm check to see which is shorted and replace that board to fix the set. if it is the address board (one that plugs into boards with lots of chips addressing each horizontal line of screen) you need to check all the address buffer chips. make sure there is no little pin sized hole burned into one of these chips or it will blow out your new address board.
other names for boards
address = Y sustain
sustain = Z or X sustain
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Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://electro-medical.blogspot.com/
http://electronicshelponline.blogspot.com/
To some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced.
SOURCE: LG TV powers on but there is no picture
Contact any service technician; or the authorized service center. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electro-medical.blogspot.com/
http://electronicshelponline.blogspot.com/
In most cases, the main board might have to be replaced. If so, a software [firmware] update too might be necessary.
Fault at its main digital board. Short circuited component/s at it.
Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://electro-medical.blogspot.com/
http://electronicshelponline.blogspot.com/
To some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced. To some models of sets, all these section circuit will be integrated at its main board. If this is the case, you have to replace the main board.
Main controller board is probably, or it could be the lcd display panel itself.
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