Samsung UN65KU7000 Backlights

[muscatintechguys]

Hello. I have a Samsung UN65KU7000 where the backlights were not working. If the TV was in a certain position, the left strip of back light would turn on but would be intermittent. I took the back off and wiggled on the cable that runs from the Power Supply board to the LED Strips. Now the left side of the TV seems to be working correctly with no cutting in or out, but the right LED Strip has not turned on at all.

Any recommendations on checking power supply or other components before I try to take the panel off?

[CapLeaker]

Re: Samsung UN65KU7000 Backlights

check the voltages on each backlight string. Also some clear, straight shot quality pictures would help, so we can see something. Then we can go from there.

[muscatintechguys]

Re: Samsung UN65KU7000 Backlights

So I got some voltages for cable running from the power supply to the LED lights -

1. 216v
2. 118.7v
3. 216v
4. 118.7v
5. NC
6. NC
7. 118.6v
8. 47.8v
9. 118.6
10. 47.8v
11. I had to put red probe on ground - climbs to 200v and drops and goes back up
12. Same as 11

[R_J]

Re: Samsung UN65KU7000 Backlights

Looks like a problem in the panel
pins 1&3 are common, pins 2,4,7 & 9 are common, 8 & 10 are common, 5,6,11 & 12 are not used.
One string connects between 3 & 4, the other string connects between 7 & 8
1&3 are the supply voltage, 8 &10 are the return.
3&4 led string has about 100v across it, 7&8 has about 70v. I would geuess the fault is wihin the panel, maybe where the strips connect together.
Do be very carefull if you remove the lcd panel.

[muscatintechguys]

Re: Samsung UN65KU7000 Backlights

I'll be attempting to remove the panel tomorrow. I'lll let you know how it goes. Thank you for the reply!