Hello everyone,
The repair isn't finished yet and I'm still working on it, but unfortunately, we had a minor flood due to heavy rain.
So I have no choice but to wait to continue the work until the damage to the house has been repaired and I have everything back in my small workshop.
I'll continue as soon as I can.
ChristianBr01
Member
Last Activity: 06-02-2025, 02:49 AM
Joined: 04-21-2025
Location: D
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I can't believe. It was a small 0603 capacitor on the pcb where the cof strips are connected to. I couldn't find something faulty on the TCon but had fluctuations on every single voltage line.
PSU was 100% ok and Mainboard too. Had only problems on the TCon board...
I was just guessing and checked all the capacitors there for short circuits. I found a shorted capacitor on the left side.
I removed it with hot air and replaced it with another one from a TV board. Everything's working fine again.
What a strange behavior for a shorted capacitor. Have not expected this......Leave a comment:
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It's definitely inside the monitor. I opened it up and inside it is completely a LG. It was a pain to remove the small ribbon cables from the metal case cause they have been glued to it.
Everything looks quite good but I was expecting the fault an the T-Con and I truly believe that I'm right with my thoughts.The Voltages from the PSU to the T-Con are all stable but the Voltages on the T-Con are not.
I will write them all down and post them here cause I need here some help from someone with some experience.
I've expected some fluctuations and that something is pulling a...Leave a comment:
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It is weird.
What I already tried is go through Dells suggestions on their website to solve the problem but no changes.
I've changed the ports from DP to HDMI and replaced the cables but no changes.
Tried to reset the Monitor through OSD, change the frequency in Linux and Windows a couple of times with the same result.
Disconnected the Desktop and used my Laptop as Video Source... everything stayed this same. But if you look at the picture,
you'll see that the lines appear as soon as the the panel has to display a picture on screen, even if it's a OSD without...Leave a comment:
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Dell 34 inch U3419W Monitor with thin stripes on partial screen
Hello everyone,
I have a Dell U3419W Monitor that has some thin stripes on a part of the screen since Tuesday.
This lines cover about a third of the screen and appear for 2 seconds before disappear for another 2 seconds.
This repeats the whole time. I have not opened the case yet cause I had no time, but will try to fix it on this weekend. For me, it looks like a problem on the TCon... Am I right?
Does someone have seen this before?... -
A new IC is already ordered but has not arrived yet. Will replace the IC as soon as I get them.
Davi.. when this shorted ADIM PIN goes to the MB, could this be the reason why I burned the IC on the MB like I mentioned in post #13?
I replaced the TI IC and the MB is working cause the typical Samsung startup sound is there...Leave a comment:
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I know, I know Diah... You've been right and I did it the wrong way. Lesson learned, I hope 😉
I tested the IC in Beep mode and than measured the resistance to ground. I have a 0,1 Ohm resistance to ground on pin 14 and this is not wright!
I've desoldered the IC and measured the resistance between pin 5(GND) and pin 14(ADIM) off the pcb and the result is still the same 0.1 Ohm. On my replacement IC the resistance between GND and ADIM is in high KOhm range.
Will check the rest later but I have a another problem since Tuesday with my PC Monitor. Will post it "[B]Troubleshooting...Leave a comment:
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Yes, this TV has Edge LED Strips so there were only two to replace. The left side had one LED with black marks on it. It was definitely burned ...
I believe that it's like on the primary side. Everything was ok and I had no shorts there except the Fa6B19 IC. On the secondary side I found a short on the MAP3612B IC
and replaced it with the only one I had... but i tortured this IC so many times with my hot air station for learning purposes that this thing isn't working as it should anymore.
Haven't expected that I would need exactly this one so badly now.Leave a comment:
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Thanks for the information. Since I don't understand everything yet, I'm very grateful for any explanation.
I've ordered the IC on Ebay cause I've found no other source for it. Not even AliExpress wanted to deliver this IC it to Germany.
The Resistors are ok but I have exactly the same on a Samsung junk board so I can replace them if needed.Leave a comment:
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I've checked them a few times and they are good. I truly believe that my ic is not working properly. Got the ic from a junk board I used for soldering practice.
Unfortunately I soldered and desoldered this little thing too often... and unfortunately it's the only one I had of this type...
I guess I have to order another one from Mauser or RS.. or Aliexpress. A bit frustrating when you always don't have something in stock.Leave a comment:
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My apologies for the late respond but I had some long workdays and no time to go on with the repair.
Yes, this are the diodes I mean. They have around 183V and this looks good in my opinion. What I found out is that the Mosfet driver - MC MAP3612B - was shorted. I have replaced it with the only one i had but I've had already solder and desolder this thing for a couple of times... for learning purposes 😊
I don't know if this driver is really full functional or not... I hope and it looks so.
the loud buzzing noise is no more but still no backlight. I hear the typical...Leave a comment:
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My Backlight strips have finally arrived, so I replaced the faulty strips with the new ones. One LED was burned and this was on the left side. Was a little bit scared but I did everything very slowly and carefully.
The swap of the Backlight strips was successful but I have no luck with this TV 😪 The already mentioned Buzzing noise is still there and there are more faulty components. The voltage on the diodes is OK but not one FET. This FET is exectly for the Backlight strip that had the shorted led on it.
So.... the search goes on. Have to check every single component in this circuit...Leave a comment:
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Thank you very much Davi,
needed a little break but have ordered the Backlight strips and now waiting for them to arrive. Didn't know that a faulty Backlight can cause so many more defects. I couldn't explain to myself why so many different things were damaged
Thanks for your explanation... will disassemble the TV tomorrow and hope not to damage the panel. Honestly... This TV is so overly complicated and the whole electronic is designed not to be repaired by someone. But this is just a beginners opinion.Leave a comment:
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Got my ICs yesterday. Incredible fast shipping via FedEx but incredible shipping fees too. Couldn't await to solder the new IC
on the board and so I did yesterday evening. Checked everything twice for shorts once again... nothing!
Then I've plugt the Connect Box and standby light appeared back again. First I measured all the Voltages on the Board and this
time I got my 5V, 3.3V, 1.9V, 0.9V and 12.8V on the transistors :-
Pushed the power on button and the Connect Box started to click.. and nothing more. Same like before but with all needed Voltages on the Main board....Leave a comment:
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Thank you all for your reply. Have ordered the burned IC and now I am waiting for it.
Have checked the entire region around the chip for short but couldn't find anything else. Hope this was the only defective IC.
Thanks a lot for the information an the p-ch FET. I couldn't find a datasheet for this Samsung MOSFET.
Samsung's quality decreases, that's right. I follow some youtube repair channels and try to learn from them. They are talking quite a lot about
the decreasing quality and how the manufacturer over complicating the circuits/systems.For a beginner like me,...Leave a comment:
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I borrowed from the company I work for a UNI-T 260A thermal camera. I was really excited but my attempt to find the faulty component went terribly wrong.
I found a spot on the board where something was heating up but very slowly. The Connect Box tries to turn the TV on and then stops. So I've pushed the TV on button for about 4- 5 times to localize the heat spot better.
And then.... something lightens up so quickly that I could not react. This feels so bad. I am really shocked till now. Not what I wanted.
The good is, the PCB is not damaged. I've de-soldered this ic and cleaned...Leave a comment:
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Hello Davi.p,
forgot to attach some pictures of the One Connect Box and the One Connect Cable that I write about, sorry for that.
The TV has only one connection on the back and this is for the One Connect Cable. This model of the One Connect Box provides the TV with everything it needs over the One Connect Cable. Have attached some pictures of my model from a tear down clip that I found on youtube. It's from a 43 inch model but the Box is the same.
There are 3 Mosfets on the mainboard and about 5 on the BL PSU and non of them is shorted. But one on the mainboard, a P-Ch 30V 50A,...Leave a comment:
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First of all thank you so much for your kind support.
I put the Backlight on my list cause I have no Backlight Tester. I am a little bit scared about disassembling everything and "maybe" braking the panel.
es, I checked the fuses and they are good but I will do it once again, to be 100% sure.
@KYBOSH
I have no FLIR but in the company i work we have a UNI-T thermal camera. Maybe I can get it for a weekend and then check the board.
The One Connect Box and the One Connect Cable are both good. Already mentioned that I have checked both on a 50...Leave a comment:
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Tried all combinations but result remained the same.The 13V on the connector are missing and therefore on the psu.
Thank you!Leave a comment:
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Hello Diah,
no short on IC 1503
Voltages on Pins
P1: 3.3V - P2: 1 - 1.5V depends on clicking inside the One Connect Box
P3: 0V - P4: GND
P5: 0V - P6: 0 - 0.7V depends on clicking inside the One Connect Box
P7: 3.3V - P8: 3.3V
Thank you for your help!
I thought, i found something shorted but I was wrong. On the picture with the whole pcb are 3 yellow marks. A Coil and 2 ICs. The coil ist connected with on side to a diode and with the other to ground.. so it´s ok.
On the left ist a small sot23-6 IC1100...Leave a comment:
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