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Samsung ue55h6200 sound but no display

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Turnip:
Hi Nix,

With the back off you can usually see if the back lights are working, light leak out making it obvious. If not, but there's sound, it's 99% that there are duff Leds in the back light array.

With the screen off you can check each Led with a 9v battery and 1k series resistance (in case they're 6v leds), but only by flipping the lenses off, as otherwise it's difficult to get contact through the strip insulation.

Otherwise, China does a good cheap tester where you can check a single diode or an entire string without needing bother with voltage or current, the device indicating what voltage Led fitted. Should you have an O/C Led, you'll need take the lenses off to find which one it is unless there are burn marks on the strip.

Been there - Good luck - Chris.

Nix125:
Thanks for the info turnip much appreciated.

LEDs are definitely not producing any light. If one goes does that  effect all of the LEDs hence why having to test strips? Why would the flashlight test fail is this because you cannot always see with a flashlight in the dark?

Kind regards

Turnip:
Hi Nix,

Strips are in series, sometimes connected direct to a two lead feed, or in other sets with multi leads, strips are again in series.

With just one duff Led - The inverter can sense either an O/C Led or a shorted one. Admit in some cases 6 can go S/C before the inverter susses and cuts the power.

With an O/C led (Usually poor initial soldering which can lead to a track burn) the inverter cuts straight away.

Hence it's useful to have a tester to check each strip individually.

Wouldn't worry about the flashlight test as your Leds aren't alight, proving the issue - Chris.

Nix125:

so received a second hand tcom board today that I purchased from ebay for 11 quid delivered. When I connected it up and turned on the power three blue leds lite up then a noise that sounded like a hdd booting could he heard and the tv is now working perfectly. Didn't realise that the board had lights as the broken one none lit up.


Kind regards

downunder:
If all are lit, T-con is OK. If any are out, could be the T-con or panel.
Also with most Samsungs, disconnecting the main from the power supply should result in backlights working. If so, main board is faulty. If not then it could be power supply or backlights faulty.           Bruce

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