I was given a 32" Samsung TV for free because it kept turning itself off. I checked the PSU and all caps seemed fine, no obvious burn marks. Then I found this video and after that I managed to find the same broken solderjoint. It was barely visible, I dont think I would have noticed without this video. Thanks for the help!
I had the same problem and after changing the capacitors on the power board, the backlight would still not stay on for more than a minute or so and so I put the TV in the spare room and forgot about it. Today, a year later, I decided to have another go and was again getting nowhere until I saw your video. I inspected the transistor legs with a magnifying glass and the solder looked ok but with nothing to lose, I resoldered them and fantastic, it worked. Thank you very much. I was about to throw the TV out.
Hello there. Thank you veeeery much mate. I could fix my tv after having watched your video. I found the exact same defect on the very same solder joints. It's now working fine. Thanks again. Christian
Spot on! Checked all caps and they looked fine, only 5.2v being supplied to main board and the power board looked bowed/curved slightly which led me believe tracks had gone and was going to purchase a second hand one. Then watched this and sure enough dry and cracked solder joints on point 802. Big thanks Volt!! saved me a few ££££s. .
Thanks for the inspiration. I have a Samsung TV that had already had the power board replaced once already, but this second time Samsung would not fix it. The symptom was a flashing standby light but the tv would no turn on. If I unplugged the the main board from the power board (which usually turns on the LEDs on a Samsung), but they flashed. I could not visible see anything wrong with the power board, but after seeing your video, thought it would be worth reflowing some of the solder.... To my surprise... when put back together, it worked again. Hopefully posting this here will help someone else out too. My power board model is Samsung BN44-00801A
Grazie al tuo video sono riuscito a riparare il mio Samsung del 2008. a volte si accendeva tranquillamente a volte lampeggia led 5 volte poi morto. grazie mille buon lavoro. ciao dall'Italia. Thanks to your video i managed to repair my 2008 samsung. sometimes it turned on fine sometimes the led flashes 5 times then died. thank you very much good work. bye from Italy.
That cold solder joint problem might be caused by the transistor heating up when the TV is ON and then cooling down when it is turned OFF causing the solder joints to expand and contract. I would put a small heat sink on it.
Same issue here, also removed the dried epoxy, some of it had high resistance when measured with the multimeter, and also was the ones with high resitance were dried out af.
You need to apply +5 V DC to the PS_On/Off pin to turn on the board itself, right? I have a PS board (L32S0X) from a Samsung S32D850T PC monitor that is probably defective too.
Hi there! I have a Samsung BR/DVD player with power board V 170- S DPN and when I turn on it goes into protection mode and off. I ve checked the PB and saw a pin blown near MOS 11N80C3 is the 2 pin (DRAIN) and solder is gone with a part of the wiring. Before the pin the current goes tru a diode 1 N 4742 A 12V / 1 W and that is bad also. You thing that might be the cause? I need to replace the diode and resolder the pin what do you think. Where do I get a schematics for this type of Power board? I ve measure the voltages during that 10 seconds on and off time and the values are not good . Instead of 27 V I have only 8 V instead on 2.5 V I have -11 V and that s not right. I also cleared the SMD with tiny cloth and alcool, and the front panel with switches also. I ve looked out for bad soldering . Also the silicone paste around the mos is kinda drained out on the board.Maybe u can give a hint. Thanks!
Hi, What do you suggest for the following problem I am facing: I have the powerboard BN4400932B of a Samsung TV, which says the Standby power to be 11.8V. I disconnected the board off TV and checked the Standby power to be ok I.e. about 11V, when I connect the board on the TV the Standby power drops to 4.5V. What could be the reason?
Oh... Thank you. I had recently watched your other videos and I saw the probe master leads video... I visited their website and I found out they are shipping worldwide ... What was the shipping costs to Romania ?
I have searched for a schematic or ANY information on a Samsung power supply board LJ44-00187A also marked LJ44-00188A and PSPF321501C and PSPF421501C and can find nothing . This is from a 42" plasma rebranded as Changhong. All the voltages are ok but with no load connected it draws excessive current and brightly lights a 150W load lamp in series with the mains. With a 75W series load lamp it just does a cycle of relay clicking. I am puzzled that there is nothing on Google about this board.
Looks like the RoHS strikes again. I've definitely seen capacitors that look good and measure bad. One was a Nippon Chemicon which are supposed to be good but when I tested it it was only measuring about 70% of its rated value.
yup ROHS strikes again and about the capacitors that's what i mentioned in the video, it can happen but on this occasion I just had a feeling it was not about the capacitors since all the rails were missing.
I had a siimiar issue to this, where there was no 5VSB voltage (so also no standby LED) & it turned out to be a Schottky diode had gone short-circuit. Replacing the diode fixed the issue.
Should I find myself in that situation (and I did previously) yes it can be done. It's enough to understand the architecture and you can usually figure out the important stuff.
Hello my board has been burned in the section where the CM810 the blue ceramic capacitoris is located. So my question is what type of capacitor is that to replace it. Thank you all
Master Oogway was said to master Shifu: ..."One often meets his destiny on the road he takes to avoid it."... in other words, the real reason of the broken solders on almost all three pins is exact that elastic/plastic/solid glue that was applied on the component. Put it between the legs and board it apply a HUGE amount of force when temperatures change, it expand and contract at every gradient of temperature. So what the eevblog clown keep saying with the silastic applied on components it is not always right. Let the TO220 component hang on his own feet, it is just a constant small weight, it will NOT "flapping in the breeze", unless somebody play ping pong with the set or change channels with the fist/foot. I had saw an interesting video at MrCarlsonsLab: th-cam.com/video/yy8NS2zejhQ/w-d-xo.html , where some stiffening glue apply in the old electronics in years become electricaly conductive... Right repair is to remove the component clean that garbage from its feet. Heatsink? I dont know depend of the circuit design... maybe work in saturation and it not need... it not seen any colour change of the board due to the overheating of the transistor. Good luck man.
Interesting view and I think you might be right, that hard glue could certainly be expanding/contracting at a different rate. There is also the fact that the two lower joints we're cracked and those we're the ones who got all the glue..
+fredlllll it isn't as entertaining as a more complicated repair but it is what I found in this case.. Sometimes these easy repairs are a great way to relax :-)
i also enjoy fast repairs, i dont always have to time to watch a 20 minute video of fixing a problem. and yup, its always nice to work on easy to fix problems
Bonjour, ma télévision SAMSUNG LE32M86BD après la voir allumé est de couleur blanc blanchatre quel est le problème ? quand je tape dessus cela reviens normallement
I was given a 32" Samsung TV for free because it kept turning itself off. I checked the PSU and all caps seemed fine, no obvious burn marks. Then I found this video and after that I managed to find the same broken solderjoint. It was barely visible, I dont think I would have noticed without this video. Thanks for the help!
I had the same problem and after changing the capacitors on the power board, the backlight would still not stay on for more than a minute or so and so I put the TV in the spare room and forgot about it. Today, a year later, I decided to have another go and was again getting nowhere until I saw your video. I inspected the transistor legs with a magnifying glass and the solder looked ok but with nothing to lose, I resoldered them and fantastic, it worked. Thank you very much. I was about to throw the TV out.
Hello there. Thank you veeeery much mate. I could fix my tv after having watched your video. I found the exact same defect on the very same solder joints. It's now working fine. Thanks again. Christian
Blowing fuses. Found the bridge rectifier shorted (a TS4B05G big chip). I had given up but was inspired by your video. Thanks VoltLog.
Spot on! Checked all caps and they looked fine, only 5.2v being supplied to main board and the power board looked bowed/curved slightly which led me believe tracks had gone and was going to purchase a second hand one. Then watched this and sure enough dry and cracked solder joints on point 802.
Big thanks Volt!! saved me a few ££££s.
.
Thanks for the inspiration. I have a Samsung TV that had already had the power board replaced once already, but this second time Samsung would not fix it. The symptom was a flashing standby light but the tv would no turn on. If I unplugged the the main board from the power board (which usually turns on the LEDs on a Samsung), but they flashed. I could not visible see anything wrong with the power board, but after seeing your video, thought it would be worth reflowing some of the solder.... To my surprise... when put back together, it worked again.
Hopefully posting this here will help someone else out too.
My power board model is Samsung BN44-00801A
Thanks for the step by step instructions. My screen works now. Great video!
Thanks for the vid, any idea why Samsung tv keeps burning the power supply board, I have changed it twice and burned them all?
Just curious what power supply and magnifier you use? Thanks!
Grazie al tuo video sono riuscito a riparare il mio Samsung del 2008. a volte si accendeva tranquillamente a volte lampeggia led 5 volte poi morto. grazie mille buon lavoro. ciao dall'Italia.
Thanks to your video i managed to repair my 2008 samsung. sometimes it turned on fine sometimes the led flashes 5 times then died. thank you very much good work. bye from Italy.
Where can I get the schematic?
Just fixed my workshop tv before I was about to tear-down for parts. Thanks for making the video. I was exactly the same problem on mine...
That cold solder joint problem might be caused by the transistor heating up when the TV is ON and then cooling down when it is turned OFF causing the solder joints to expand and contract. I would put a small heat sink on it.
Ken Franco Or just throw on some real lead solder...
which I did :-)
Same issue here, also removed the dried epoxy, some of it had high resistance when measured with the multimeter, and also was the ones with high resitance were dried out af.
You need to apply +5 V DC to the PS_On/Off pin to turn on the board itself, right? I have a PS board (L32S0X) from a Samsung S32D850T PC monitor that is probably defective too.
Very Nice video! You saved my old TV! You are a great man!
Hi there! I have a Samsung BR/DVD player with power board V 170- S DPN and when I turn on it goes into protection mode and off. I ve checked the PB and saw a pin blown near MOS 11N80C3 is the 2 pin (DRAIN) and solder is gone with a part of the wiring. Before the pin the current goes tru a diode 1 N 4742 A 12V / 1 W and that is bad also. You thing that might be the cause? I need to replace the diode and resolder the pin what do you think. Where do I get a schematics for this type of Power board? I ve measure the voltages during that 10 seconds on and off time and the values are not good . Instead of 27 V I have only 8 V instead on 2.5 V I have -11 V and that s not right. I also cleared the SMD with tiny cloth and alcool, and the front panel with switches also. I ve looked out for bad soldering . Also the silicone paste around the mos is kinda drained out on the board.Maybe u can give a hint. Thanks!
Hi, What do you suggest for the following problem I am facing:
I have the powerboard BN4400932B of a Samsung TV, which says the Standby power to be 11.8V.
I disconnected the board off TV and checked the Standby power to be ok I.e. about 11V, when I connect the board on the TV the Standby power drops to 4.5V.
What could be the reason?
What's the brand (name) of your test probes that you are using with Fluke?
Probe Master
Oh... Thank you. I had recently watched your other videos and I saw the probe master leads video... I visited their website and I found out they are shipping worldwide ... What was the shipping costs to Romania ?
I don't remember it was a long time ago :)
Worked for me - I resoldered the same transistor joint and TV turns on now. Thanks.
awesome!
I have searched for a schematic or ANY information on a Samsung power supply board LJ44-00187A also marked LJ44-00188A and PSPF321501C and PSPF421501C and can find nothing . This is from a 42" plasma rebranded as Changhong. All the voltages are ok but with no load connected it draws excessive current and brightly lights a 150W load lamp in series with the mains. With a 75W series load lamp it just does a cycle of relay clicking. I am puzzled that there is nothing on Google about this board.
Very nice video.
Which forums do you read about such problems and where do you look for schematics?
Thanks for the help
I just google for the problem I have, no particular place.
Thank you very much! Very good video and explanation.
Looks like the RoHS strikes again.
I've definitely seen capacitors that look good and measure bad. One was a Nippon Chemicon which are supposed to be good but when I tested it it was only measuring about 70% of its rated value.
yup ROHS strikes again and about the capacitors that's what i mentioned in the video, it can happen but on this occasion I just had a feeling it was not about the capacitors since all the rails were missing.
Thank you
I had a siimiar issue to this, where there was no 5VSB voltage (so also no standby LED) & it turned out to be a Schottky diode had gone short-circuit. Replacing the diode fixed the issue.
nice!
What is it with Schottky diodes going short in TV's these days? I've seen loads of them.
Hi brother, my samsung BN44-00192A sound takes a while to work, please help me. Thank you
would u be able to fix a Power supply without a schematic?
Should I find myself in that situation (and I did previously) yes it can be done. It's enough to understand the architecture and you can usually figure out the important stuff.
Hello my board has been burned in the section where the CM810 the blue ceramic capacitoris is located. So my question is what type of capacitor is that to replace it. Thank you all
un60h6203af replaced LED backlighting they work I tested and I have picture when I hold a flashlight upto it but the LEDs won't turn on
Amazing analized, more vids like this, sir :)
Nice video as usually
+Christian Christiansen thank you!
Thanks
Really nice! Thanks
Thx
God bless
this circuit not output 24v and 12v what is fult
Master Oogway was said to master Shifu: ..."One often meets his destiny
on the road he takes to avoid it."... in other words, the real reason of the broken solders on almost all three pins is exact that elastic/plastic/solid glue that was applied on the component. Put it between the legs and board it apply a HUGE amount of force when temperatures change, it expand and contract at every gradient of temperature. So what the eevblog clown keep saying with the silastic applied on components it is not always right. Let the TO220 component hang on his own feet, it is just a constant small weight, it will NOT "flapping in the breeze", unless somebody play ping pong with the set or change channels with the fist/foot.
I had saw an interesting video at MrCarlsonsLab: th-cam.com/video/yy8NS2zejhQ/w-d-xo.html , where some stiffening glue apply in the old electronics in years become electricaly conductive...
Right repair is to remove the component clean that garbage from its feet. Heatsink? I dont know depend of the circuit design... maybe work in saturation and it not need... it not seen any colour change of the board due to the overheating of the transistor.
Good luck man.
Interesting view and I think you might be right, that hard glue could certainly be expanding/contracting at a different rate. There is also the fact that the two lower joints we're cracked and those we're the ones who got all the glue..
recently also had a dry solder joint to fix on the psu of my 3d printer :P
+fredlllll it isn't as entertaining as a more complicated repair but it is what I found in this case.. Sometimes these easy repairs are a great way to relax :-)
i also enjoy fast repairs, i dont always have to time to watch a 20 minute video of fixing a problem. and yup, its always nice to work on easy to fix problems
fredlllll SK!skxkskesygfdzttjfjdyfyhgfudgtepyvfokfgkhgahxeettklshgghhrdsahfgbhjg
Bonjour,
ma télévision SAMSUNG LE32M86BD après la voir allumé est de couleur blanc blanchatre quel est le problème ? quand je tape dessus cela reviens normallement
Have you ever messed with a BN44-00775A power board
I once heard that switching power supplies cannot be turned on without a load (because it can fail). But I see that you turn it on and nothing happens
Have an clickingsound on the powerboard of my UN65JS9500. Any ideas? @
when you looking always very good, you can spent money. :-)
thanks!