Samsung UN55H8000 sound but no backlight no video

[Max514]

Hi all,

Ok so I have this beautiful un55h8000 samsung tv with sound but no video nor backlight. When turning the set on the red light blinks 5 times.

The screen shows no damage and backlight turns on when I disconnect the power supply from the main board. The tcon board only has 2 out of 3 leds on.

I came across this page and followed the different steps: https://techhometravel.com/samsung-u...ight-no-video/

• Unplugging the main board cable at the power supply >>> backlights came on.
  
• BLU_ON signal from the main board >> 3.5V
  
• The tcon board only had two out of three LEDs lit up >>> When disconnecting both ribbons to the panel, the third LED still did not light up.
  
• Powering up the TV with only one side connected at a time >>> no backlight nor picture.

At that point while I was performing the test it seems like my tcon fried (ceramic fuse) and would not start again (0 blue light). When turning the set on the backlight would light on but still no video.

So I ordered a new one (hopping this was the faulty part anyway), replaced it and I am now back to square one with no video / no backlight.

Thinking the issue comes from either the power supply board or the mainboard. Do you know how I could isolate the culprit here, since it looks like it's not a tcon issue? I read 12.86v on all the 13v outputs but not sure what to check now...

[yokoono]

Re: Samsung UN55H8000 sound but no backlight no video

The LED off the t-cone indicates that the t-cone is protected. You have a short circuit in the panel. Depending on the type of t-con, protection can be undone to determine which part of the panel is defective. Some TVs only turn on the image when both ribbons are connected. First of all, look for how to cancel the protection of the t-cone.