Samsung UN60D6420UFXZC Not turning on

[Wellington1]

Just joined this unique and very informative forum and my first tv in need of some help is a 60" Samsung led that does the all too familiar relay clicking with no power up - I have yet to plug it in as I purchased it from the previous owner knowing the problem - I paid a few dollars for it although free would have been better I decided on a calculated risk that it is fixable without spending too much.


Knowing that Samsung tvs have their own problems I am hoping it might be something straight forward, like perhaps the main board or power supply issue. I have a friend who, although not a technician does know his way around these sets having repaired a good number as a hobby.


I have yet to bring the PS board to him, along with the main board and go through them - all I know beyond the failure to power on is that the set was fully functioning and the screen had no issues, of course I have to take the previous owner's word for it.


A few images - I noticed some of the screw mounting locations are not used, is this critical? I have no idea if someone had the PS board removed but never hurts to ask!


Is there anything I can do myself - I have had very little experience diagnosing etc. but do have a multi meter - even if I do not know how to fully use it! So at this point I have yet to plug the tv in and try to turn it on so any suggestions are very much appreciated! The set was manufactured in Dec. 2011 if it matters. My understanding is that generally the LED sets do not typically suffer from bad capacitors on the PS board but I could be wrong, certainly it would be great if that were the case.

What can be done to ensure that the screen is alright? Any particular tests? After bringing the tv home in my car ( just fit without the stand ) I want to be sure it is alright, just to be safe even though I handled it with due care.



I read another thread where the blue tooth module prevented the tv from turning on - same relay clicking as well. I noticed some screws missing on the PS board that secure to the back panel so not sure if perhaps someone previously removed it and did not use all of the screws, just wondering!

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Interesting result when I plug the A.C. cord into the wall outlet and then was a few feet away, not looking at the tv as I pressed the on/off function on the upper right corner of the remote, the owner's manual mentioned this was for the remote back lighting but perhaps I was mistaken as I suddenly realized the tv screen was on, flashing all sorts of patterns , some with words on them but it happened quite quickly and lasted for perhaps 10 - 15 seconds or so before going blank, at this point I could hear the relay cycling on the P.S. board at intervals lasting around 20 - 30 seconds.


I wish I could have taken a picture of the screen but it looked fine as the entire screen was producing the various images all over. I have nothing connected to the HDMI inputs, which is all I would use.



The tv has been unplugged for at least a month so not certain if I waited for part of the day if it will reproduce what I saw, but it appears the panel is alright, just displaying whatever.

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

So, I unplugged it and waited 10 minutes and then reinstalled the power cord and when the tv turned on there was a symbol displayed in the lower right hand area that said " NO HDMI 2 INPUT" within a dialog box - the entire screen was evenly dark with no lines etc.-within a few seconds it started to roll up the screen until there were all sorts of thinner lines as well as thicker ones all over including multiple images of the "NO HDMI" dialog box as it flickered until turning off, again, the screen itself certainly looks fine and I assume with no input signal it displayed those odd images.

From behind the tv I could see the entire screen was back lit through various small openings in the rear metal mounting panel due to the bright white of the leds - I will definitely try and take a picture of it if possible.



Update: After the third try it now simply does the rely clicking after being plugged in - no response from the remote, tv remains off. Well, at least it tried do something initially!

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Anyone have any idea about the possible issue - since it did power up if briefly and the back light did function as well this appears to narrow the cause. I have been searching here and on the internet for possible answers but nothing yet.


At this point I have not tested voltages etc. I am certain that the tv can be functioning once again without too much effort or cost.

[attainteddragon]

Re: Samsung UN60D6420UFXZC Not turning on

if you disconnect the lvds connector (it goes from the main board to the t-con) and apply power, you should get backlights but no picture.

[Nick's Tvs]

Re: Samsung UN60D6420UFXZC Not turning on

Disconnect the cable between the orange board aka power supply, and the main board, aka green board with HDMI ports. Plug it in and check results. This will auto turn on the power supply and backlight. If you have a good power supply and good backlight, then it will stay on indefinitely. I would suggest leaving it on for 20 or so minutes to make sure all those are working fine. If they are, then do what attainteddragon suggested and disconnect the T-con board from the main board by removing the LVDS cable. If the backlight turns on again, and the tv stays on, then I would suggest connecting a cable box, or DVD player, and blindly cycle through inputs until you hear sound. Once you do, once again test it for a bit to make sure it doesn't turn itself off.
If it does not, then indeed you may have a bad T-con or bad panel.
I do believe you may have a bad main board however.

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Thank you everyone for the suggestions - have been away for a time and just checked so will try what was outlined. Before checking here I did plug the tv in and it does power on automatically within 10 - 15 seconds without touching any power buttons on the tv or remote - staying on perhaps a minute.


I started another similar thread detailing a bit more information but should have checked this post, hopefully I can isolate the issue before too long. Kind of hoping it is not the main board! I suppose though for what I paid even at that the tv would still be worth fixing. From what I saw of the even led lighting and OSD that appeared initially the screen is function fine, as was mentioned by the previous owner, it just powered off one day doing the relay clicking on the PS board.

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Just tried the cable disconnect from the PS board to the main board and the back light does indeed function - tv also auto powered on. So far it has been 10 minutes and will continue letting it run.

Can anyone let me know how to disconnect the LDVS ribbon cable from the T con board? Do I leave the cable from the PS board to the main board disconnected as well?

Also, without knowing the specific issue if it is the main board would heating it in an oven and doing a solder re flow be worth looking into? I have read where it has solved cold solder joint issues.


Thank you again guys. As much as I enjoy my Panasonic U50T plasma I still would like to get the Samsung working and use it for non critical viewing. When looking at the lcd screen from above it looks a bit uneven, imagine a result of the edge lit leds.The entire screen is working, no lines and no dead pixels showing.

The tv is still functioning after at least 20 minutes, will leave it on for awhile longer to be certain.

[CapLeaker]

Re: Samsung UN60D6420UFXZC Not turning on

can you post a picture of that?

[vinceroger69]

Re: Samsung UN60D6420UFXZC Not turning on

sounds like a possible bad main board

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

I seem to be leaning that direction too - worth checking the T con just to be certain of course. The connector has me a bit stumped, just not sure exactly how it is released and I do not want to break it!


CapLeaker - are you referring to the screen?

[petehall347]

Re: Samsung UN60D6420UFXZC Not turning on

is it the eeprom ?

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

I wonder about the two flashes on the front of the tv when it was unplugged, as I mentioned when the PS board relay double clicked the power on led flashed simultaneously three separate times in unison before I imagine capacitor (s) were drained. It must mean something as the power on led will normally never indicate anything when the tv is on. This is with everything connected of course.


Image of the ribbon connector - never had experience with this type.

[heavymachines]

Re: Samsung UN60D6420UFXZC Not turning on

It should work as shown in edited pic

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

heavymachines - Success! A big thank you for taking the time to show me - so simple once you know but it looked trickier than it was and one thing I do not need is a broken ribbon connector!


Now I just need to find out if the connector from the PS board to the Main board is reconnected for the T con test, not quite clear on that part as Nick's Tvs mentioned.

[heavymachines]

Re: Samsung UN60D6420UFXZC Not turning on

heavymachines - Success! A big thank you for taking the time to show me - so simple once you know but it looked trickier than it was and one thing I do not need is a broken ribbon connector!


Now I just need to find out if the connector from the PS board to the Main board is reconnected for the T con test, not quite clear on that part as Nick's Tvs mentioned.

Yes main connected with just lvd flat ribbon disconnected.

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Reconnecting the cable to the Main board from the PS board and with the T con LVDS cable disconnected there is no back light, no front power indicator, just the PS board relay clicking once every 30 seconds. When I disconnected the ac power cord the relay double clicked twice with a 15 - 20 second interval between and I noticed the front power led flashed twice quickly three times in succession - did this twice in conjunction with the double clicking relay.


Going to reconnect the T con cable and disconnect the PS/Main board cable again and double check the back light function. Are we to assume this is likely a Main board issue?

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

Image of the lcd panel - it looks more even than shown, never easy to duplicate with a camera. When there was the OSD showing briefly "no input signal" it was clear and sharp and when the lines appeared just before shutting down they were separate from the OSD, not going through it, just that everything kind of bounced and scrambled and then a shut down and relay click.

[CapLeaker]

Re: Samsung UN60D6420UFXZC Not turning on

I almost think you have more than one issue. I'd like to see those lines on the OSD.

[Wellington1]

Re: Samsung UN60D6420UFXZC Not turning on

CapLeaker - I perhaps worded my description inaccurately - when the " no input signal" and " no HDMI 2" came up on the screen when the tv is first plugged in ( after being unplugged for at least 1 week ) they were perfectly fine, the lines that soon appeared were separate and did not go through the OSD, it was then that everything "bounced" or scrolled before the tv simply shut down. So far after a second or third unplug/ plug in attempt, with about 10 minutes between each the tv ill show just thicker colored bars and lines and after that will not respond, as in not turning on. I know it will not turn on via the remote or power button on the tv.


I have no doubt the screen is not an issue, the previous owner mentioned that it was working fine until it decided to turn off and do the relay clicking routine. I could try and get an image of it next time, I do not think it is possible to actually have a video signal from say a dvd or blu ray player - I could have something playing I suppose plugged into the HDMI 2 slot and perhaps will see something before the tv shuts down with a minute or so, assuming that it responds while receiving a video signal, if not I would think it is a Main board problem?

Still wondering what the T con board disconnected from the Main and no back light represents. I initially, before finding this forum, asked a tv technician selling components on Ebay about what I was experiencing and his initial impression was the panel, suggesting I unplug the T con board completely and see if the relay stops recycling and the back light is on. so I assume the LVDS cable from the Main as well as the ribbon cables to the panel. Knowing what I saw on the screen the panel is functioning properly. If the Main board is gone then I would think supplying a video signal would do nothing, perhaps when plugged in the tv might not turn on?