First off, thanks for all help or advice you can provide me.
So, I'm having a problem with my LG- TV, to be exact a 50PG100R.
One day, while watching TV, the display just turned black.
Sound still works fine and power led does what it's supposed to do (so the TV isn't just turning off).
Display lights up a little bit, like a the backlight turned on (can't show with a photo, because camera somehow isn't picking the light up) and the pixels look like they are lit up a tiny bit.
After around two seconds, the display changes to a darker color, but is still lit up (probably the Mainboard dimming the display)
What I already did:
-Checked for faulty capacitors: all of them seem to be fine.
-Checked all fuses I could find (including SMD ones): no blown ones.
-Checked all connectors for tight fit: no change after doing so.
-Checked voltages going to Mainboard:
16,5V and 12V are both 0V in standby and 16,5V respectively 12V when turned on.
5V is always 5V
RL_ON (guess this is ReLay ON) and VS_ON are both 0V in standby and 3,3V when turned on.
-Jumpered Ext_Auto_Gen on the control board, but nothing (as far as I understood, jumpering Ext_Auto_Gen should give test patterns on the display)
quite boring until now, isn't is? But now comes the interesting part:
-Va measures 69V and Vs measures 201V (as far as I understood the panel lable, Va should be 65V and Vs 193V
-Vzb measures 105V to 112V (should be 100V)
--Vy measures (interestingly prositive) 167V to 195V (measured over resistor labled -Vy, prositive probe connected to lead labled (+), negative probe connected to the lead labled (-)) (should be -195V)
-Vsc measures 122V to 138V (measured like -Vy) (should be 135V)
-+15V going to X-Sustain measured 15V
(105V to 112V (etc) means that the voltage is constantly changing, although this could also be some sort of switching)
When disconnecting either the Y-Buffers or the X-Sustain from the Y-Sustain, or the Y-Sustain completely,
-Va normalizes to 66V
-Vs normalizes to 193V
--Vy, Vsc and +15V still measure the same values as before
So, I guess the Y-Sustain board is defective in some way (although I could be completely wrong with that), but buying a new one isn't really an option because the cheapest one would cost around 55€, without a guarantee that the board actually works.
So I'd like to try to fix the board myself, but don't have any idea where to start, or if it's actually the Y-Sustain thats faulty.
Anyway, any advice and assistance will be greatly appreciated.
PS:If additional or more detailed pictures are needed, I can take them.
PPS:I don't know much about plasma TVs, so I might have named some board wrong, so I labled them on a picture for better understanding.
PPPS:I'm new in this forum, so if I did something wrong, please tell me and I'll try to do better next time.
So, I'm having a problem with my LG- TV, to be exact a 50PG100R.
One day, while watching TV, the display just turned black.
Sound still works fine and power led does what it's supposed to do (so the TV isn't just turning off).
Display lights up a little bit, like a the backlight turned on (can't show with a photo, because camera somehow isn't picking the light up) and the pixels look like they are lit up a tiny bit.
After around two seconds, the display changes to a darker color, but is still lit up (probably the Mainboard dimming the display)
What I already did:
-Checked for faulty capacitors: all of them seem to be fine.
-Checked all fuses I could find (including SMD ones): no blown ones.
-Checked all connectors for tight fit: no change after doing so.
-Checked voltages going to Mainboard:
16,5V and 12V are both 0V in standby and 16,5V respectively 12V when turned on.
5V is always 5V
RL_ON (guess this is ReLay ON) and VS_ON are both 0V in standby and 3,3V when turned on.
-Jumpered Ext_Auto_Gen on the control board, but nothing (as far as I understood, jumpering Ext_Auto_Gen should give test patterns on the display)
quite boring until now, isn't is? But now comes the interesting part:
-Va measures 69V and Vs measures 201V (as far as I understood the panel lable, Va should be 65V and Vs 193V
-Vzb measures 105V to 112V (should be 100V)
--Vy measures (interestingly prositive) 167V to 195V (measured over resistor labled -Vy, prositive probe connected to lead labled (+), negative probe connected to the lead labled (-)) (should be -195V)
-Vsc measures 122V to 138V (measured like -Vy) (should be 135V)
-+15V going to X-Sustain measured 15V
(105V to 112V (etc) means that the voltage is constantly changing, although this could also be some sort of switching)
When disconnecting either the Y-Buffers or the X-Sustain from the Y-Sustain, or the Y-Sustain completely,
-Va normalizes to 66V
-Vs normalizes to 193V
--Vy, Vsc and +15V still measure the same values as before
So, I guess the Y-Sustain board is defective in some way (although I could be completely wrong with that), but buying a new one isn't really an option because the cheapest one would cost around 55€, without a guarantee that the board actually works.
So I'd like to try to fix the board myself, but don't have any idea where to start, or if it's actually the Y-Sustain thats faulty.
Anyway, any advice and assistance will be greatly appreciated.
PS:If additional or more detailed pictures are needed, I can take them.
PPS:I don't know much about plasma TVs, so I might have named some board wrong, so I labled them on a picture for better understanding.
PPPS:I'm new in this forum, so if I did something wrong, please tell me and I'll try to do better next time.
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