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reference to internal leds What voltage is a 3-LED light from a LED-TV?

As above the gentleman is asking for operational voltages etc, my question is (refer to my pic)

The apparent white circles may be due to overcharge given short the several dead LEDs.
Is it possible the dead LEDs are having a negative (aesthetically) effect on the panel?

enter image description here

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The white circles are caused by the LEDs not being aligned correctly with the light guide or diffuser. The backlight of a TV is an array of LEDs that illuminates a diffuser/lightguide that shifts the point source of the LED into a uniform white background. The spacing between the diffuser and lights is critical for it to function. If they become misaligned you get the effect you see there. Usually this can be fixed by removing the casing from the TV and putting the diffuser back into place.

That won't fix the dark voids though where the diodes have failed though, so probably the TV is junk unless you want to go about replacing the diodes.

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  • \$\begingroup\$ Fair assessment. Upon inspection however would suggest something a little different, ie not diffuser misalignment. Reason being, the diffuser set was still factory taped and secured in position to the frame edges using a sort of slot capture, rendering any movement within the set impossible \$\endgroup\$ Mar 31 '20 at 4:53
  • \$\begingroup\$ If you can see the individual LEDs, then something is wrong with the diffuser. Did the TV ever work correctly? If so, I would double check the spacing between the diffuser and the LEDs. Note that while the diffuser moving is more likely, it is worth checking that the LEDs are in the right place. Whatever broke some of the diodes could have moved the rest out of position. \$\endgroup\$ Mar 31 '20 at 5:28
  • \$\begingroup\$ Is there any possibility that the dead Leds are causing over powered in the rest.. there's only 32 leds, and 4 or 5 are dead. Only 2 wires from the motherboard run the lot I'm not really sure how the space could be issue, it's all secured in a housing with all the plastic pins to maintain distance \$\endgroup\$ Mar 31 '20 at 10:07
  • \$\begingroup\$ Probably not, since TVs use constant current LED drivers. Even if the LEDs are running a few percent brighter, that wouldn't explain why the diffuser isn't working. \$\endgroup\$ Mar 31 '20 at 13:57
  • \$\begingroup\$ I might add, when watching tv, you can only see the dots every now and then.. actually is still watchable. While gaming however, not noticed at all (tv was recent purchase for driving sim) \$\endgroup\$ Apr 1 '20 at 1:56

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