This is a LCD TV brand EMERSON, model LC320EM3F and is completely death.
At first revision, we detected some bad components in the switching power source:
Switching MOSFET K10A50D, RESISTOR 0.19 Ohm, 2W, transistor switching controler 2SC5344, Zener Diode 1ZB36 (36V) and the 4A fuse.
I had the SM of LC320EM9 model, so, the values of the components are different.
I replace them all twice and they always broke again! FRUSTRATING!
Then I realyze that changin the values nearly to the LC320EM9 model, I would obtain better results (see FILE ATTACHED)
I replace the 0.19Ohm resistor by a 0.39Ohm, maximizing the pulse received for the control transistor, for that purpose, also changed the 2.4KOhm resistor for 5.6KOhm. The switching MOSFET used was IRF640 replacing K10A50D, and transistor 2SC5344 was replaced by 2N5551. Finally we add a Zener diode not included in original board (marked with blue circle) limiting the colector voltage and gate voltage to 26V.
For short, when we connect the power cord, every thing was fine, except than voltages at secondary of main transformer, was only 3.2V DC in all rectifiers.
Found a diode in short-circuit (circled in red), replaced it and BINGO!, the TV return to live again!!!!
I Hope it serves as a nice experience for the future.
I have this LCD TV which has a very white screen, the picture is visible. I could not find any fault on the CCFL Lamp inverter and was suspecting the T-Con panel of failure. The T-con panel is integrated in the control board. What i did is using "freeze it" cold spray i sprayed one of the IC's and it cured the fault. Perhaps the IC needs to be replaced. The part number is AS15-G. This component is not available for purchase in south africa and i would need to import it from china. This part is a LCD voltage buffer.
A fenti TV-n a következő "kép" látszik:
Már pár napja szenvedek a fönt leirt készülék hálózati részével és semmire se jutottam. A hibajelenség egyszerű, elszáll a hálózati meghajtó tranzisztor. Eredetileg S2000-A2 volt benne, én BU2508AF-t tettem helyette. Megy kb. 2-3 órát és kezdődik a mese az elejétől. Átnéztem a kondikat, meghajtó tranzisztorokat, minden jó.
Volt-e valakinek problémája evvel a hálózati résszel???
Előre is köszönet mindenkinek