Chosen Solution
I have a Samsung M/N UN50H6203AFXZA that will not turn on. The standby light comes on and when ‘turn-on’ is attempted (remote control or joystick switch) the light blinks off 5 times then goes off and stays off. This also happens as the set is plugged into AC. Press the remote or switch again, and the light comes back on. If the PS cable to the Main Bd. Is disconnected and then the set is plugged in, the backlight DOES NOT COME ON. I have not detected any images on the screen. Here’s some voltage readings, but first let me say that they may be a little off since all I have available to me currently is a very old meter. All readings are from the PS board. CNM803 connector: (cable to Main Board) Referenced to chassis ground UD 13.6 VDC PWM BLU. 13.6 PS ON 13.6 GND 13.6 GND 0.0 Readings are the same when the cable to the Main Bd. Is disconnected.
CNL802 connector (cable disappears into edge of the frame that I have not removed yet). ( I assume they supply power to the LED back lights ) Referenced to chassis ground. 1 - D+ 380 VDC -Stays the same when connector is pulled 2 - D+ 380 -Stays the same when connector is pulled 3 - S1- 35 -goes to zero when connector is pulled 4 - S2+ 35 -goes to zero when connector is pulled 5 - NC 0 6 - S2- 17 -goes to zero when connector is pulled 7 - S3+ 17 -goes to zero when connector is pulled 8 - D- 0 9 - D- 0
Note: Voltage at jumper JP817 is labeled as “STB:8V and ON:13.0 V”. Mine is 13 V all the time. Can any one help me determine which board or component needs replacement? What are my next diagnostic steps?? I have included some photos.
@bearcatboy …. if you unplug the main board and the lights dont come on, its usually a sign of a bad led or many. if you unplug your leds from your power supply board, you should be able to check voltages there. if the voltages are matching the silk screen voltages listed on the board, its your backlights. if not, power supply board. if the tv doesnt turn on without the backlights plugged in ( i believe it should) then you can force voltage into the backlights with a led tester you can find online. heres a link for the device: https://www.amazon.com/TKDMR-LED-Lamp-Ba… using this will turn on the backlights and you can see if there is a section dark or pulsing on or off. if this is the case, led’s confirmed. if not, power supply board will be the answer as disconnecting the main board on samsungs force backlights on if functioning. hope this helps, post back for any further assistance.
