Re: Samsung UN55KU6300FXZA

Normally I wouldn't reply to an old thread but it's already resurrected.

I ended up guessing and buying a replacement power supply board online and that did the trick. TV has been working fine for the last year or so. I didn't really dig into the design of the board but I could see even on a DMM that the voltages weren't stable so that seemed like a good guess.

Appreciate everyone's help on this. I totally would have tested/changed out the diode at the time if I had this info. Thanks all!

Re: Samsung UN55KU6300FXZA

I haven't really checked every solder joint but the couple times I've been on the solder side of the board I remember thinking everything looked well wetted. I may give it one more look just to be sure. I do remember there seemed to be a lot of coating on the solder side which I thought was gross.

My first post wasn't perfectly clear, but I think at some point I checked voltages with the main board disconnected and then both with/without the LEDs connected. I will probably go back and double check that measurement tonight also.
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Re: Samsung UN55KU6300FXZA

Okay, so, thanks again to all so far for the help. I appreciate everyone's time.

I tested the two requested things tonight:

Filter caps:
I tested this with the two boards (power supply and processor) connected.
Measured main filter cap (CP806) with unit plugged in: 390V DC
Pressed the power button, and no change (390V).

CNM803 connector from power board to processor (main) board. This was done with the CNM803 connector disconnected (so the main board is not connected to the power board)....

Re: Samsung UN55KU6300FXZA

Thanks for the help so far. Here are updated test results.

Configuration: Entire system assembled, plugged in.

'Reading on' is after pressing 'on' button. I noticed no difference. My wife watched the indicator LED on the IR receiver and it blipped the same way as before each time.

Most of these oscillated - both before and after pressing the power button. I estimate they cycled every 2 seconds. Did not time with a stopwatch or scope.

Pin / Signal / Reading Off / Reading On / Note/Comment...

Hi, I've got a Samsung UN55KU6300FXZA that doesn't turn on but does show a blinking red (standby) light. When I press the power button the remote the red light blinks rapidly but faintly, pretty much the entire time I hold down the button.

Before I pay for a new power supply board I am hoping someone else can confirm my determination. Or maybe provide me other things to check before pulling the trigger on a replacement.

I haven't found schematics for the board that I have but I've read up what I can on diagnosing and repairing and have the following information:...

Re: New Members - please post your introductions here

I'm new here, my name is Dexter. I enjoy fixing pretty much anything, I have had good success repairing my own cars, small engines, appliances, etc. Experience with electrical circuits and systems. I have plenty of general knowledge and am hoping to learn a little about specifics of certain systems (Samsung TVs at the moment).