Chosen Solution
Hi, I have a 50” Samsung TV model number UN50TU8000FXZA, I dont know much history about the TV. There is a date of 2019 on the power supply board. I have done the following troubleshooting so far: Symptoms: When plugging in the TV, the Samsung logo comes on the screen, and within 1-2 seconds the logo becomes partially garbled, and additional 1-2 seconds the tv turns off and then turns back on, starting the cycle again. When plugging in the tv, i can see the leds on the back go through 3 stages of brightness and on the last (when they are the brightest) the logo comes on. I reseated all internal cables with no change in symptoms. Steps done so far: I checked all capacitors on the power supply board, no bulging tops.I left the TV plugged in for about 5 minutes and the cpu on the main board registered 125 degrees F. Seems hot for a resetting/non functioning cpu, but i dont know what to expect.Disconnected the cable to the main board. Plugged in the TV, the LEDs come on and I measure the following voltages in order at the LED connector on the power supply: 209V, 171V, 171V, 96V.On the power supply board, the voltages for the main board connection are as follows: 1-G, 2-G, 3-13V, 4-3.3V, 5-13V, 6-3.3V, 7-13V, 8-0-1.4V, 9-13V, 10-0V, 11-G, 12-0-1.6V. Pins 8 and 12 fluctuate between 0 and 1.4/1.6 volts, it spends about 3 seconds at 0 volts, then changes to 1.4/6 and drops back to 0. Does anybody know if these voltages are in spec? the pins at 13V are correct, there is a label on the board, but the remining pins are descriptions, not voltages. I’m wondering if pin 6 should be 5v? Anybody have any other steps I can try? I can’t really find much in the way of schematics online, so i’m kind of stuck as to where to go next. I really hate to throw money at parts, i’d rather have make an educated guess. My initial thought from what i can tell is the power supply seems ok, it is puzzling i dont see 5V anywhere, which is what drives a lot of electronic boards. I suspect the main board but hoping there is a way to further diagnose.
Yup same problem haven’t had the TV for 3 years apparently this is a known problem with the 8000 models they all seem to do it no matter the TV size. Power Supply and cpu board are pretty cheap so I’m going to try this first and if that doesn’t work it’s going in the trash. Smh I’m never buying a Samsung tv again. Will update with results
Here’s what Samsung says to do: https://www.support.com/how-to/how-to-fi…
A power fluctuation may be the reason for the error. Also don’t forget to take your TV adapter(if present) for a physical examination and see if the capacitor on the power unit is working.
did you replace the power control board? seems like the drop in voltage is stemming from there
