Very nice video keep them coming my friend.I'm learning a lot from them .Don't worry about that one unhappy fake tv repair boy because men don't act like that.
You're a Bad man Bigdog - respect. Your videos are very instructional for component level troubleshooting. I've been looking at your videos - keep it up you are helping lots of people.
Great video I have a 55 inch lg that gives the same type of reaction off the power supply board. Yet all the led strips light up when the power is first on. Then they go off.
you prolly dont give a shit but does any of you know of a way to get back into an instagram account?? I somehow lost the password. I love any help you can offer me.
@Dalton Bruce thanks so much for your reply. I got to the site on google and im waiting for the hacking stuff now. Looks like it's gonna take a while so I will get back to you later with my results.
Fully agree excellent brother the way you illustrate make possible to see & understand more clearly.. now if l need any info on tv.. bigdog is my official guide..
Excellent video!! Keep them coming Bigdog! You've helped me troubleshoot over 10 different tvs I've come across already. What's up with all the critics on here? Almost every board I've ever worked on has underrated components on it and who cares if it is not original as long as it works and its safe.
I am looking for a service manual/schematic of this BN44-00669A board. I have the same issue with the blown resistors and require the values. PDF schematic would be awesome
@@im14u2noSame resistors as in the video? According to bigdog in the video, they were 1 ohm each. 3 resistors in parallel, at 1 ohm each, equals 0.33 ohms. 3 resistors in parallel means they can pass 3 times the current, so if one resistor was 1/4 watt, 3 resistors in parallel can handle 0.75 watts.
There is over 100 volts at the second line negative lead!!! This might be a surprise...maybe advise people to use right arm only for probing with multimeter negative on chassis as you show. Thanks for the videos..
I have no DC voltage on the powerboard LED / Backlight connector........AND I don´t see a picture/logo when shining with a sharp light on the LCD screen. So I´m wondering if you did have a picture or not in your case when lighting up the screen with a flashlight. Greetz from Holland!
@@bigdog8882 Thanks for the comment, but that´s not the case, Maybe the backlights are good. BUT I don't know if the ignitian of the backlight, like other powerfunctions is by the processor on the mainboard. I have read in a servicemanual from LG company that in case of -no logo no video and no sound- the mainboard has to be replaced. Getting the right mainboard is rather difficult. So I think it is gonna end in buying a new UHD TV with Android and no longer spending money on this one. LG Tvś have a lifetime of nearly 7-8 years and are nowadays produced by robots in china. In that case there is nothing for me to complain! Greetz and best wishes from Holland!
Hey your second power supply is the one I’m working on. I also have two of these are the same model but made a year apart from each other. On one tv change the tcon board on to the led strips. Now they don’t light up. Now I know what your saying to tace back the voltage.
Great video @bigdog! I have an issue with my tv that I don’t know if it is just a backlight issue or it is a resistor one like in your video. Do you really see a little bit when you use a flashlight to see the screen or it can still be pitch black like my tv? Thank you for the help!
Hello I love all Your videos and i see you are able to replace a SMR with a color coded one, i am glad i do not have to use the same resistors. My Naxa NT-520k has sound but no back light.the backlit lights up when i use the tester across the 2 lead wire. i can not find a schematic for This Naxa TV however The Board number is Cv3458h-Aso which looks similar tot the Rca board The driver board using the multi purpose meter reads 08.1 on the Naxa TV but in stand by mode 12.0 V,i am guessing the Led strips are ok but not sure where to test. i still have more testing to do i did the test with the over head light (not flashlight) and i can see the menu screen
I have the same TV (oops, almost, un60j6200afxza), when plugged in, the LED's just flash - no pic, no sound...PS issue? All of the LED's appear to be lighting up from what I can see from the back side, all of the light in the holes look very even...just flashing. I have not been able to find this symptom after going through all of your awesome videos...thoughts? Thanks brotha!
It seems that wall mounting and/or the user running the set with the backlight at maximum setting is a major contributing factor in these backlight failures. The wall mounting seems to prevent adequate ventilation and makes the LED strips overheat and fail.
Hello Bigdog, I have an unpredicted problem on a UE55F6100... I checked everything, replaced one led that was dead on a strip but still clicking and no power up. I manage to make the tv runs for hours fine with no problem by removing the led connector and plugging it after the tv is powered on.... its really strange! don't know where to search, don't want to replace the powerboard as all working correctly if i plug the led connector after powering the tv on. the powerboard is L55X1QV_DSM BN44-00625C thank in advance for your help!
Interesting and will probably help me fix my TV. There is a reason for the three resistors though. Each one is sized to act as a "fuse". The reason for 3 instead of one is that a current surge could take out one resistor but the other two would still supply the power needed. More than likely what happened in this TV is that as LEDs failed, resistors opened up until they were all "popped". Using one large resistor will make the TV work, as seen, but that safety factor is now gone. Might let the majik smoke out of the PSU on the next problem.
Yep, just said that above, they were meant to blow in case of overcurrent. But they are in parallel so are sharing the current. If one blows, the other two will quickly follow.
Hey BigDog, what up bro, I have the same tv. 2 LED strips appear to be non functioning in the top left corner. If I have the brightness or the backlight turned up to high, all the other working backlights start flashing off and on and then will stop if I turn down the backlight and or brightness. Would those 2 burned out LED strips cause this problem? Thanks in advance.
@@bigdog8882 thanks big dog, It works perfectly now. Replaced all the LED strips. This samsung was easy to take apart and fix. Works perfectly now and thanks for all your videos. They are a big help. Happy New Year.
The cable is called LVDS.. The resistors are probably what is known as current sense resistors. The LED current draw of the LEDs is translated into a small voltage that the control IC uses to know how to regulate. It is called feedback. The total resistance is usually .7 to 1.0 ohms.
It's quite old now so likely found the correct resistor values by now. Obviously ok to test for further issues but the correct resistors would have needed replacing. Incidentally if you Google the power unit model you can usually find a schematic to confirm component values and to help with fault finding. Good job though and keep it up.
SAMSUNG MODEL # UN60J620DAFXZA VERSION # NS02 PICTURE - Red, black and blue colored display with slow blurry movement. and No sound What should be the problem ? Please advice for the parts i need to order.
Check the 5 volt standby pin on the Power Supply plug going to the Mainboard. If no voltage on the plug then replace PS. If u do have voltage on the plug; especially the standby voltage, then U could possibly have a bad Mainboard.
Look for a light tan coloured board if it’s not there someone has taken it out that’s why no standby light Check fuse in plug Check list (if the board is there) Look for burnt or damaged components Check 5amp fuse near mains socket Check the bridge rectifier (slim black device which looks like a corner has been cut off next to the top heatsink) Check mosfets on topside of board Check diodes Check mosfets on the bottom One to look for is a 50R380 common to blow
Haven't got a clue have you, you should not be allowed near electronics, heard of pulse width modulation have you? what do you think controls the brightness of the back light?
I believe if you remove the power cable between the power supply and motherboard, the back light should light up as soon as you plug in the power cord.
If your always unhappy with how I do repairs and solder, watch someone else's channel and leave little immature negative comments on their video. OK Mr. Perfect!
@Sodder Bridge I believe the point of this video is to show there is more than one way to skin a cat. The board had obvious signs of overheating. He even mentioned that and said. This was not a perfect solution but rather an alternative.
Would you know what my panel model number would be, since there is no sticker on my panel, I need to order replacment LED strips, SAMSUNG Model # UN60H6203AF TYPE- UN60H620 MODEL CODE- UN60H620AFXZA VERSION- HH01 S/N- 02Q43CDF500105R
@@bigdog8882 yes I am studying to become a software engineer through virtual education opportunities opened by the pandemic. If anyone is reading this and want a PhD from Harvard or any other Ivy League University or College now is the time if you are unable to afford the tuition. The colleges are set back tremendously due to covid and they are actively helping new students apply for the financial aid and everyone is getting approved. No pay back options are available. 12 months and 32 credits and you have a real PhD from Harvard or Yale.. Or any of them.
Yeah they were actually too small in the first place. Remember, those resistors got almost 400v going threw them. I guess it was an afterthought on Samsung's part. Thats why they put 3 smd resistors in parallel on the bottom instead of just using a higher wattage one on top of the board. They just use one B+ line and just one feedback circuit to light up a 60 inch tv with 6 rows of led strips. Efficient and Cost Effective for them I quess. lol
The 3 resistors act as a fuse just in case LED backlight is shorted. It uses 3 as SMD resistors at higher wattage will use up more space if you use 1 with bigger wattage.
Over a period of time the led's short out 1 by 1 and constantly pull too much current from the led circuit on the power supply, Thats when I showed the dark spot on the board. Eventually when that last one shorted it probably popped those resistors (which were probably overheating anyway) before it got to anything else.
@@bigdog8882 Understood & I'll keep it in my data bank in case I have a similar issue & visible evidence of the board getting hot in spots was there. Wonder if they didn't have a surge protector or if it just happened from overuse thru the years.