Solved! What controls the backlight on/off on an LED television? Need a technical question answered!

Status
Not open for further replies.
Nov 2, 2018
3
1
10
1
I don't know that this is the appropriate place to ask but if anyone can answer my question it would be greatly appreciated--I don't know if I should junk this TV or not.

I have a 60 inch Samsung LED smart TV. The model number is UN60J6200AF. It has no picture, but sound, and the flashlight test reveals a working image. This model is known for LED strip failure but this is not the case if my testing is correct.

At first I suspected the power board. It has four wires going to the LED panel configured as 1-Ground-Ground-2. Power wire #2 has 450 volts, #1 has 0 volts.

When a wire is bridged from #2 to #1, the LED panel illuminates and the TV and backlight are completely functional? I replaced the power board thinking it was the problem, but it did not fix it.

The other visible boards in the television are a main board with the video connections and a T-Con board below. I do not see a separate backlight inverter or LED driver. Are either of these components primarily responsible for switching the backlight on/off? There is no visible damage to either of them.
 
Nov 2, 2018
3
1
10
1
For anyone that comes across this same issue--I found my own answer after searching for voltage readings on the power board. The main and only connection from the video board/main board sends a 5v signal to the power board through connector CNM803. Without proper voltage from this connector the power board will not supply power to the LED strips.

https://www.pcrichard.com/images/promos/12Samsung%20CE%20Newsletter%20Dec%202012.pdf
 
Reactions: sirkitbreaker
Nov 2, 2018
3
1
10
1


I'm thinking that it's broken down like this. Power wire #1 and ground are for the LEDs, and #2 and ground are for the panel since the display works fine. There doesn't appear to be a separate driver for panel/LEDs and it's all integrated into the power board. When you bridge them you're siphoning display power over to the LED strips. I don't know. I am wondering if the main video board has to supply the signal to the power board in order to switch the backlighting on and it is just not sending the signal.
 
Nov 2, 2018
3
1
10
1
For anyone that comes across this same issue--I found my own answer after searching for voltage readings on the power board. The main and only connection from the video board/main board sends a 5v signal to the power board through connector CNM803. Without proper voltage from this connector the power board will not supply power to the LED strips.

https://www.pcrichard.com/images/promos/12Samsung%20CE%20Newsletter%20Dec%202012.pdf
 
Reactions: sirkitbreaker
Status
Not open for further replies.
Thread starter Similar threads Forum Replies Date
jnojr Streaming Video & TVs 1
C Streaming Video & TVs 0
M Streaming Video & TVs 0
K Streaming Video & TVs 1
RexIsReckless Streaming Video & TVs 1
P Streaming Video & TVs 2
V Streaming Video & TVs 0
M Streaming Video & TVs 0
M Streaming Video & TVs 4
D Streaming Video & TVs 1
T Streaming Video & TVs 1
E Streaming Video & TVs 6
R Streaming Video & TVs 0
R Streaming Video & TVs 0
R Streaming Video & TVs 2
W Streaming Video & TVs 3
A Streaming Video & TVs 2
C Streaming Video & TVs 2
S Streaming Video & TVs 3
I Streaming Video & TVs 1

ASK THE COMMUNITY