Samsung curve 49 BN44-00807A

[Afickgenius]

hi need ur advice to my problem.. all the voltage are fluctuation.. primary and secondary. what is cause that so. all the transistor seems ok no short at all. when i unplug cablle to main board sometimes backlight turn on and some not.. voltage 13v is goind to 8 then 3 back to 13 just like that

[Diah]

Re: Samsung curve 49 BN44-00807A

some one with bad soldering experiences worked on the Powerboats. need to rework all in clean way under good magnifier.

[nomoresonys]

Re: Samsung curve 49 BN44-00807A

When you unplug cable to mainboard (always do it with tv unplugged from power then plug power cord into powerboard) the backlights should stay on every time, not just sometimes. Check all your solder joints, look them over real closely and give them the wiggle test to see if any are loose, reflow any that look bad, can google for bad solder joint images if needed, is a good place to start I guess.

[nomoresonys]

Re: Samsung curve 49 BN44-00807A

Use caution not to touch any of the capacitor leads unless you're sure they are discharged, they can hold a big charge for while even after tv is unplugged, 450 volts IS DEADLY.

[Afickgenius]

Re: Samsung curve 49 BN44-00807A

Use caution not to touch any of the capacitor leads unless you're sure they are discharged, they can hold a big charge for while even after tv is unplugged, 450 volts IS DEADLY.

alright sir..

[Afickgenius]

Re: Samsung curve 49 BN44-00807A

backlight driver at pin 1 , i think the input .. see 13v 10v and 8v..
what is maybe the spoiler..

[Afickgenius]

Re: Samsung curve 49 BN44-00807A

my power supply ac line also not stable 233 - 240 fluctuation.. is that cud be the cause of output 13v got fluctuation..

sorry for my very good english..

[budm]

Re: Samsung curve 49 BN44-00807A

If you run the power supply board by itself without cable connected to the main board, what are the Voltages at the power supply board connector that goes the main board?
What is the history of the TV?
Did someone try to repair the board before you?

[Hamie]

Re: Samsung curve 49 BN44-00807A

https://www.badcaps.net/forum/showthread.php?t=90116

Check my thread here.
Not 100% that it's causing your fault but it's fairly common with your fault symptoms.

[Afickgenius]

Re: Samsung curve 49 BN44-00807A

[QUOTE=budm;1022372]If you run the power supply board by itself without cable connected to the main board, what are the Voltages at the power supply board connector that goes the main board?
What is the history of the TV?
Did someone try f

voltage witout board .like i attach pic above? something like cycling between stanby and power on.. several led wer fault n id replace them off.. and now i at the mainboard the small fuse been defective.. and now when rhe psu connected to mainboard.. at stanby the voldtage maintain at 12.8v.. but when u turn it on those backlight become disco club on and off

[Afickgenius]

Re: Samsung curve 49 BN44-00807A

https://www.badcaps.net/forum/showthread.php?t=90116

Check my thread here.
Not 100% that it's causing your fault but it's fairly common with your fault symptoms.

i just try pul out the diode.. the testing the psu without that ic.. same gos up and down..