Samsung LED TV UE40D6517WK will not turn on

[henrikek]

Hello!

I have a samsung tv modell: UE40D6517WK. The problem is that the TV will not turn on.

When I connect powercord the red LED light up and I measured 5,3 volt on (B5V) pin 19 connector CNM803 on PSU modell: BN44-00427A. Everything looks good.

If I disconnect connector cabel betwen mainboad and PSU the backlight light up and everything looks good.

When i try to turn the TV on the relay click in PSU and the red LED light start to flash normaly 5 times and then get off. No backlight lights up. I measured the folowing on connector CNM803:
1 - OD_Level - 4,66 volt
2 - PWM_DIM4 - 0 volt
3 - OD_ON - 4,58 volt
4 - PWM_DIM3 - 0 volt
5 - GND
6 - PWM_DIM2 - 0 volt
7 - B13V - 12,79 volt
8 - PWM_DIM1 - 0 volt
9 - B13V - 12,79 volt
10 - B13V - 12,79 volt
11 - Vamp - 12,79 volt
12 - BLU_ON - 0,1 volt
13 - Vamp - 12,79 volt
14 - GND
15 - GND
16 - GND
17 - B5V - 5,31 volt
18 - A5V - 5,32 volt
19 - B5V - 5,31 volt
20 - PS-ON - 3,33 volt
After 16 seconds the PS-ON voltage is dropping the relay clicks and repeats every 16 seconds.

I does not get any voltage on BLU_ON or PWM_DIMx so i think I have some trubel with the mainboard modell: BN94-05105K (BN41-01587E), but I am not sure? If the mainboard is fault do anyone have any tips which commponent on the mainboard that be fault?

[CapLeaker]

Re: Samsung LED TV UE40D6517WK will not turn on

12 - BLU_ON - 0,1 volt
The main board isn't turning the back lights on. Like you figured already out, the back lights did come on when the main board is disconnected from the PSU. That is because the PSU has a pull up resistor.
If you follow the BLon / PSon back, it is generated at the main IC on the main board. So you'd need a schematic and then probably find 90% of the time out that the main IC doesn't produce BLon.

[henrikek]

henrikek

Thanks for four quick respond. Does anyone have the shematic for BN94-05105K and BN44-00427A? Or the service manual for UE40D6517WK TV?