LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

[Jermo133]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Here is the picture of all the boards, and The model numbers I see. The rating on the C8110 cap is 100v

Thanks!

[budm]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Here is the picture of all the boards, and The model numbers I see. The rating on the C8110 cap is 100v

Thanks!

Thanks, at this just wait for the LED tester so we can find out what is going on with the LED strips.

[Jermo133]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Budm, the LED tester came in today. What would be the best way to go about testing the LED's? Thanks!

[budm]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Remove the LED connector from the power supply board then keep red probe on +VLED 1, black probe on -VLED1 one at at time.
Do the same for the +VLED2 and the -VLED2.
4 tests total.

[Jermo133]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Okay, I tested and I see lights with one test on the +LED1 and one of the -LED1, nothing on the rest of the test. I check the +LED1 a third time and now the lights don't come on at all. So I am assuming this means that I need new LED's?

Thanks again!

[Rso30]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

Budm,
I am having the same issue, the only difference is that my voltage does not go down to 33v. It does for a literal moment, then it stays at 52v. I get around5.8v on the vled returns. The other difference is on c8017 and the one next to it only read 52 on the + and nothing on the -. Finally, I get nothing on c9815 + or - and the same for the one next to it.

[neilc6]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

LF and LB series have high rates of failure in the LED strips. The heavier lenses also get loose over time and can fall off leaving bright spots. In this model, the backlights will flash when an error is detected but if a LED fails open circuit, they will not flash. Proper repair is to replace them with new strips. Lots of sellers on ebay and Aliexpress. https://techhometravel.com/lg-ln-ser...ed-backlights/

[handsworth]

Re: LG 55LF5700-UA.CUSDLH - Black Screen, can see image with flashlight test

In order to test the leds in this tv with the tester, Remove all the connecting wires from the strips. There is a small U shaped clip on the ends of two of them. Put one of them on the end of one complete strip. Not sure if its the A or B strip since I cant remember now. Test that strip now. It will light up the entire strip. Repeat process on other 4.