I picked up one of these for the super low cost of free as it didn't turn on. The panel is in seemingly perfect condition so I figured its probably worth the time and parts to restore to service.
When you plug in the unit the standby led turns on a steady red. When you press the power button the standby LED blinks red several times then goes out. Several seconds later the standby LED will turn back on, steady red and you can repeat this cycle for as long as you want. There is no sound at any point. The panel does not respond in any way.
My first problem is for the life of me I cant find a schematic for the power supply board itself. I found quite an extensive one for the IO board but I suspect the power board isn't outputting power in the first place.
I've already checked VA and VS test points on the power board before and after power on and neither test point provide any meaningful output voltage (0.10v - 0.20v). I've done some spot checks around the board and while I have a few diodes which are either bad or zener diodes (no schematic makes this far more complex to know for sure) and a few resistors that are out of spec I cant see what the problem may be without more information. I have access to and experience with a DMM, soldering and scope equipment I just need info at this point.
I have seen some threads about similar models of TV here and I have already swapped one of the main tantalum caps to rule that out but it has the same behavior before and after.
Does anyone have the power board schematic or advice on what to check next? My power board info follows.
P/N EAY62812501 EAX64863801 (1.7)
REV:1.0 2012.10.19
LGIT PCB P/N 3PAGC10113A-R
PSPI-L202A
When you plug in the unit the standby led turns on a steady red. When you press the power button the standby LED blinks red several times then goes out. Several seconds later the standby LED will turn back on, steady red and you can repeat this cycle for as long as you want. There is no sound at any point. The panel does not respond in any way.
My first problem is for the life of me I cant find a schematic for the power supply board itself. I found quite an extensive one for the IO board but I suspect the power board isn't outputting power in the first place.
I've already checked VA and VS test points on the power board before and after power on and neither test point provide any meaningful output voltage (0.10v - 0.20v). I've done some spot checks around the board and while I have a few diodes which are either bad or zener diodes (no schematic makes this far more complex to know for sure) and a few resistors that are out of spec I cant see what the problem may be without more information. I have access to and experience with a DMM, soldering and scope equipment I just need info at this point.
I have seen some threads about similar models of TV here and I have already swapped one of the main tantalum caps to rule that out but it has the same behavior before and after.
Does anyone have the power board schematic or advice on what to check next? My power board info follows.
P/N EAY62812501 EAX64863801 (1.7)
REV:1.0 2012.10.19
LGIT PCB P/N 3PAGC10113A-R
PSPI-L202A
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