led tv SAMSUNG UE40D5003 power supply+driver LED : BN44-00473A -not turn on

[ANDRASONI LUCIAN]

I have this tv with this problem: at start-up, the St.By LED flashes twice, after which it stays in St.By, sometimes the LED flashes twice in a cycle of 5 time. At the start, for moment,is present the tensions PFC = 390V, voltages of 5,2V, 12,7V and voltage for led driver, after that this tensions fall in 0. I replaced ICP801S = SPC7011F, ICM801 = FSFR1700XSL, the electrolytes caps beside these two integrated and PC801S, PC802S, PC803S optocouplers, I redo the soldering, including the smd components, "cold" measurements on components. Only the voltage St.By = 5,2V, the rest, no change. With the coupler removed from the mainboard, the backlight does not work at all. Maybe someone has encountered this problem, thank you!

[R_J]

Re: led tv SAMSUNG UE40D5003 power supply+driver LED : BN44-00473A -not turn on

What voltage do you have on CNL802? check these voltages while turning on the tv.
Pin one should be +255
You likely have a bad (open) led in the panel
Use the Search and put your model number in, there are a couple similar threads

[ANDRASONI LUCIAN]

Re: led tv SAMSUNG UE40D5003 power supply+driver LED : BN44-00473A -not turn on

Thank you very much R_J