TV Repair Questions? Ask a TV Technician
I will try to help you with this question
I understand the VS and VA are OK
How about the Vscan voltage on Y sus board(LG name this voltage -Vy)
You can measure this voltage across a resistor on the Y sustain board- not against the cold ground!
This -Vy should be around -190 to -200V( negative voltage)
If this voltage is low, then try and disconnect the Y scan buffer(s) board(s) and see if the voltage goes back up !
Please let me know what you find
Please provide the model code, something like 50PC1DRA-UA.AUSLLH, found on the label on the back cover
will have to in morning left for day
Ok the Vy Tip reads 0 Volts . Model code 50pc1dra-ua.a
Thank you for the reply
Please make sure you check the -Vy ACROSS the marked resistor!- and not having the black lead onto the cold ground
If you have a 0 reading , it means the Y sus board is not working
Please disconnect the Y scan buffer boards out of the circuit, by totally unplugging them from the connectors onto the Y sus board
power up the tv set and check the -Vy again- if still 0= defective Y sus board.
I will look up the part# for it right now
The part# for this Y sus board is:
I found it for you here:
Now, in case the -Vy goes up to the correct value about-190 to -200V after disconnecting from the circuit of the Y upper or Y lower scan drive boards= the Y sustain is Ok, and the issue is one of the Y upper or lower scan buffer boards !
part # for these boards are:
6871QDH088A upper scan buffer
6871QDH089A lower scan buffer boards
I hope this will help you getting this tv taken care of!
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Thank you, and have a great day!