Re: Samsung UN60FH6200F TV - No backlight - Please help

@budm, I was getting ~400v IIRC.

Re: Samsung UN60FH6200F TV - No backlight - Please help

Good news - I figured it out! There were three resistors blown on the back side of the board, near where the LEDs plug in. They were, from the shopjimmy picture, supposed to be 3R00 resistors, in parallel, and I'm guessing they were just acting as a fuse. I measured one at 16Mohm after desoldering it, and guessing that that was the problem, shoved a beefy 1.5ohm resistor in their place. Worked like a charm.

(Note that I will not mention the brief moment there was a 47 ohm resistor there to see if it worked... and...

Re: Samsung UN60FH6200F TV - No backlight - Please help

I do appreciate the help... I'm looking for a schematic for this one now, and I'm just not even sure where to start looking. The power to the LEDs seems low, but I've got no clue what that indicates.

Re: Samsung UN60FH6200F TV - No backlight - Please help

I appreciate any pointer. What did you do to check for a bad cap? Just look for bulging, measure voltage...?

Re: Samsung UN60FH6200F TV - No backlight - Please help

Hey! Not trying to hijack, but I've got the same TV and a related issue. 60 of the 84 LEDS were burnt out, so I just bought entire replacement strips and threw those in - no problem. Even at 20, however, they seem too dim. They kind of flicker from dim to bright, randomly, and when I tested the required voltage with my tester, it gave me ~212 (~108 per group of 3). When I measure the voltage on the connector with the TV plugged in and on, it shows ~208V, so I'm worried something is wrong with the power supply board (tested...

Re: Vizio P502UI-B1E has no backlight, no voltage from driver board to LED's

Got it.
Is there a chance that this fault is caused by another eeprom somewhere on the mainboard, and could be fixed by flashing something other than u202? We’d need a functional one for reference...

Re: Vizio P502UI-B1E has no backlight, no voltage from driver board to LED's

I’ve tried replacing the eeprom with one from shopJimmy’s site, are you suggesting that flashing it might work better?

Re: Vizio P502UI-B1E has no backlight, no voltage from driver board to LED's

Update: I’ve replaced that transistor - no effect. I forgot to test the one I took out when it was out of circuit, but it probably was fine - seeing as it made no difference. All my voltages appear fine, so I do t think it’s the power supply. I went as far as removing the panel and testing every backlight individually, and they are all fine.

At this point, I’m fairly convinced it’s the main board - but I don’t know where/why. If I hold down my power button for...

Re: Vizio P502UI-B1E has no backlight, no voltage from driver board to LED's

Adding in my two cents: I've got a board that seems very similar to al1415 - I also traced that "unknown" enable signal back to the mainboard, transistor Q210 - and measured it as bad using my multimeter. I've ordered replacements from digikey, and I'll let you know if it works or not.