Samsung LED UN55D6000SF Version # H302

[cmarroqu]

Good evening guys, I've been reading a few threads regarding this particular Samsung model that does not turn on but it's pretty exhausting being that I am brand new to all this. I like learning DIY things but this one seems like it's out of my reach.

My TV has been sitting around for a few months after it turned off and all I have now is a blinking red standby light. When I try using the power button on the remote nothing happens. If I press any other button the standby light reacts to it but nothing happens. As it sits there plugged in I can hear a faint clicking sound coming from the area of the PS board, very faint sound.

When I detached the rear cover I looked for any visible defects on the capacitors, which I hope I was looking at the right ones, but there were no visible issues (bulging or leaking). Since I read about testing the voltage and current on certain things I went out and bought a multimeter. However, I am reluctant to use it because I might make things worse.

I would like to try and figure it out myself (with your help of course) before I hand it over to a technician. i have always been a fan of these television brands but after reading these threads, I might have to make a smarter choice next time.

If anyone can help with any ideas to isolate the issue, please let me know. I've always been interested in taking classes on how these circuit boards work but. I have attached a few photos of the TCON, Main, and power Supply boards.
thanks much!

[budm]

Re: Samsung LED UN55D6000SF Version # H302

Disconnect the cables between the main board and the power supply-LED driver board then plug the TV into the AC outlet, the backlights should come on and stay on as long as the AC is applied to the TV. Try it.

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

Disconnect the cables between the main board and the power supply-LED driver board then plug the TV into the AC outlet, the backlights should come on and stay on as long as the AC is applied to the TV. Try it.

I disconnected the main board from the power supply. Plugged the tv into the outlet and no backlight. I also noticed that the red standby light is no longer on.

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

If I connect the main board back onto the power supply, the standby light comes on and blinks.

[budm]

Re: Samsung LED UN55D6000SF Version # H302

I disconnected the main board from the power supply. Plugged the tv into the outlet and no backlight. I also noticed that the red standby light is no longer on.

You not going to see any red led standby because we do not have the main board hook up, the test you have done is to find out if the power supply-LED backlights driver are OK or not, the backlights should come on and stay on when the main board is not connected to the power supply board if the power supply and the backlights are OK.
What is the power supply board P/N? BN44-?????

[budm]

Re: Samsung LED UN55D6000SF Version # H302

Read some of these threads for this model.
https://www.badcaps.net/forum/showth...ight=UN55D6000
Start with this one:
https://www.badcaps.net/forum/showth...ight=UN55D6000

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

you not going to see any red led standby because we do not have the main board hook up, the test you have done is to find out if the power supply-led backlights driver are ok or not, the backlights should come on and stay on when the main board is not connected to the power supply board if the power supply and the backlights are ok.
What is the power supply board p/n? Bn44-?????

bn44-00424a

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

I believe I read one of those threads yesterday but I'll read them again just in case I missed something.

[budm]

Re: Samsung LED UN55D6000SF Version # H302

'Start with this one:
https://www.badcaps.net/forum/showthr...ight=UN55D6000'
You are going to need to do some Voltage testing.

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

Before I start reading, just want to let you know that I tested the standby voltage with the multimeter and the voltage fluctuates up and down drastically.

[budm]

Re: Samsung LED UN55D6000SF Version # H302

Before I start reading, just want to let you know that I tested the standby voltage with the multimeter and the voltage fluctuates up and down drastically.

The A5V? How about all other Voltage (CNM803) when the cable to the main board is not connected?

[budm]

Re: Samsung LED UN55D6000SF Version # H302

btw, this board is also know for having bad soldering works on those transformer pin and the device that are attached to the hestsinks. You can see those rivet through holes where the transformer legs are soldered to which commonly failed.

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

Disregard

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

The A5V? How about all other Voltage (CNM803) when the cable to the main board is not connected?

Sorry about the delay:
The way I understood testing these pins from the CNM803 is testing the odd pins with both the TV connected to the AC outlet and the main board connected to the PS. Since the odd number pins are exposed I figure I should test them with the main board connected. Since the even numbered pins are not exposed and can obviously only be tested with the main board disconnected, I did so and the following are the readings that I got.

N.C. =0 N.C. =0
EPWM =Fluctuates B13V =0-2.3
N.C. =0 B13V =Fluctuates
BLU_ON =Fluctuates Vamp =Fluctuates
GND =0 Vamp =Fluctuates
GND =0 GND =0-2.3
A5V =5.40 B5V =Fluctuates
PS-ON =.9-2.3 B5V =Fluctuates

Not sure if this makes any sense but I will continue reading the thread you sent me. Thanks again!

[budm]

Re: Samsung LED UN55D6000SF Version # H302

So the A5V which is the Standby is steady, but the B5V and B13V which are SWITHCED power supplies that are turned on when the PS-ON is present, but your PS-ON which is the command signal from the main board is fluctuating (it is not normal) so that is why the B5V and the B13V are fluctuating. You will have to test those Voltages without the main board connected. You can disconnect the connector on the main board side and leave the connector in place on the power supply board side and probe the even pins from the back side of the connector.
You can also try having the T-CON board disconnected but all other board connected to see what happen.
https://www.badcaps.net/forum/showth...ight=UN55D6000
Look at post 6 of the link also.
BTW, you need to check and report the DCV of ps-on, blu-on, and the dcv between the two legs of the main filter cap when the main board is not connected to the power supply board.

[Andrew F. Ali]

Re: Samsung LED UN55D6000SF Version # H302

I think you have a bad LED string/s on the Backlights.....Couple of those LEDs probably open circuited.....

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

So the A5V which is the Standby is steady, but the B5V and B13V which are SWITHCED power supplies that are turned on when the PS-ON is present, but your PS-ON which is the command signal from the main board is fluctuating (it is not normal) so that is why the B5V and the B13V are fluctuating. You will have to test those Voltages without the main board connected. You can disconnect the connector on the main board side and leave the connector in place on the power supply board side and probe the even pins from the back side of the connector.
You can also try having the T-CON board disconnected but all other board connected to see what happen.
https://www.badcaps.net/forum/showth...ight=UN55D6000
Look at post 6 of the link also.
BTW, you need to check and report the DCV of ps-on, blu-on, and the dcv between the two legs of the main filter cap when the main board is not connected to the power supply board.

Thanks budm for your help. You've been a lot of help and I've MIA because of my job. Going to look into your suggestions right now and continue reading a few threads.

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

Budm,

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

I think you have a bad LED string/s on the Backlights.....Couple of those LEDs probably open circuited.....

Andrew, thanks for your input. How can I test for bad LED strings?

[cmarroqu]

Re: Samsung LED UN55D6000SF Version # H302

So the A5V which is the Standby is steady, but the B5V and B13V which are SWITHCED power supplies that are turned on when the PS-ON is present, but your PS-ON which is the command signal from the main board is fluctuating (it is not normal) so that is why the B5V and the B13V are fluctuating. You will have to test those Voltages without the main board connected. You can disconnect the connector on the main board side and leave the connector in place on the power supply board side and probe the even pins from the back side of the connector.
You can also try having the T-CON board disconnected but all other board connected to see what happen.
https://www.badcaps.net/forum/showth...ight=UN55D6000
Look at post 6 of the link also.
BTW, you need to check and report the DCV of ps-on, blu-on, and the dcv between the two legs of the main filter cap when the main board is not connected to the power supply board.

BUDM,
I tested the DCV of the even pins as you suggested and here are the following readings I got:
EPWM = 0
N.C. = 0
BLU_ON = 0
GND = 0
GND = 0
A5V = 5.40
PS-ON = 3.35

I'm sure some of the readings are suppose to be 0 but I did them anyway just in case I'm missing something or misunderstood you. I did this with the cable disconnected from the main board.

As for the PS-ON and BLU_ON, these were the readings while the cable was disconnected from the PS:
PS-ON = 0
BLU_ON = 0
Not sure if I understood the way I should test these but I tested the PS-ON and BLU_ON pins on the CNM803. As for the main filter cap, not sure which it is.
All this testing is done with the TV connected to an outlet. I'll do some further reading. Thanks again.