Samsung UN60H7150AF-has sound, no picture

[bfordz]

We have a Samsung 60" LED flat screen that suddenly lost it's picture. We have sound but can't get a picture.

No Picture what so ever, no menu, no smart hub.

I have removed the back and I can't see any physical problems or obvious signs of a failure.

I noticed the T-con board has 3 LED's; LED-1 comes on / off with the TV being turned 'on' / 'off'. LED-2 blinks one time real fast when the TV is turned on. LED-3 has never come since I took the back off. I don't know if that helps or means anything!

After some research / reading I found that if I unplug the cable from the Main board to the Power Supply board(power plug disconnected), when I plug the power back in the Backlight LED's light up.
They don't say what that means! Does that mean my "Main" board is bad? What should I check next?

I checked the voltages at the CNM803 connector at the Power Supply board:

CNM803 connector

TV Off (all connectors connected)

2-PWM-Dim4= 0.00, 1- - = .010
4-PWM-Dim2= 0.00, 3-PWM-Dim3= 0.00
6-PWM-Dim1= 0.00, 5-GND= 0.00
8-OD-ON= 0.00, 7-A13V= 10.0
10-OD-Level= 0.00, 9-A13V= 10.0
12-BLU-On= 0.00, 11-A13V= 10.0
14-PS-On= 0.00, 13-A13V= 10.0
16-grnd, 15-A13V= 10.0
18-grnd, 17-grnd
20-Vamp= 10.0, 19-Vamp= 10.0
22-grnd= 0.00, 21-Vamp= 10.0

TV ON (all connectors connected)

2-PWM-Dim4= .134, 1- - = .010
4-PWM-Dim2= .132, 3-PWM-Dim3= .133
6-PWM-Dim1= .136, 5-GND= 0.00
8-OD-ON= 3.32, 7-A13V= 12.85
10-OD-Level= 3.53, 9-A13V= 12.85
12-BLU-On= 5.16, 11-A13V= 12.85
14-PS-On= 3.32, 13-A13V= 12.85
16-grnd, 15-A13V= 12.85
18-grnd, 17-grnd
20-Vamp= 12.85, 19-Vamp= 12.85
22-grnd= 0.00, 21-Vamp= 12.85

cable from Main to PS disconnected, power plugged in

2-PWM-Dim4= 3.26, 1- - = .776
4-PWM-Dim2= 3.26, 3-PWM-Dim3= 3.26
6-PWM-Dim1= 3.26, 5-GND= 0.00
8-OD-ON= 1.35, 7-A13V=12.86
10-OD-Level= 1.34, 9-A13V=12.86
12-BLU-On= 3.21, 11-A13V=12.86
14-PS-On= 4.50, 13-A13V=12.86
16-grnd, 15-A13V=12.86
18-grnd, 17-grnd
20-Vamp= 12.85, 19-Vamp= 12.86
22-grnd= 0.00, 21-Vamp= 12.86

While trying to get 'something' on screen using the remote, not sure what series of buttons I hit (possibly Smart Hub) I got music to play from the TV, so it kind of works just no picture.

Not sure what to do / try next!

[budm]

Re: Samsung UN60H7150AF-has sound, no picture

Please put the pin name for each pin reading of the connectors so we can easily tell what each is is for.
If you have everything connected but not the 4 white flat cables between T-CON and the LCD panel, do the backlights come on?

[bfordz]

Re: Samsung UN60H7150AF-has sound, no picture

I updated my pin labeling.

NO, if I disconnect the 4 white flat cables I don't get any backlights on. TV on or off.

[bfordz]

Re: Samsung UN60H7150AF-has sound, no picture

If I reconnect all cables (main to PS board) BUT disconnect the T-con to Power supply board; the backlights come on / off with the TV.

If I turn the TV on, the backlights come on, If I turn the TV off the backlights go off.

I still can't get anything on screen; eg., on screen menu. I haven't tried an external source.

[budm]

Re: Samsung UN60H7150AF-has sound, no picture

That small connector on the T-con that goes to the power supply board is for the Backlights dimming control signal PWM1 ~ 4. So there is problem with T-CON board at this point since you disconnect that connector and you get backlights.
https://www.shopjimmy.com/catalogsea...ng+UN60H7150AF

[bfordz]

Re: Samsung UN60H7150AF-has sound, no picture

Thank you very much 'budm'

Part is on order, will update with repairs!

[bfordz]

Re: Samsung UN60H7150AF-has sound, no picture

Thanks again to "budm" for his advise on my T-con board being my problem.

These samsung parts seem to be in hi demand; I got on ebay and found a board from TVCHOPSHOP right here in MI., ordered and received it the next day!

I attached pics of the old board and then the new board, there are 3 LED's on the board and only one was lighting up on the old board (hint).

[budm]

Re: Samsung UN60H7150AF-has sound, no picture

Thanks for the follow-up on the repair, since it is high demanded board I have a feeling that these boards are not reliable and have issue, hopefully your replacement board will last.

[birdfeed]

Re: Samsung UN60H7150AF-has sound, no picture

t-con can be repaired. look for smd caps. good luck.