Re: 32 samsung lcd will not turn on just blinks 5 times
I am pretty much having same problem as the OP similar model and setup.
Model #LN32D450G1DXZA
Mainboard# BN41-0609A
Power Board# BN44-00438B
Tcon built into Panel Grrrr..
Powers on have sound but no pic.. Screen is glowing dark blue . Reacts to all remote functions. I have the movie Unstoppable playing (about the runaway train) I can see the screen reacting as the scenes change, but no picture visible. With back cover off I can see that the back lights are on.. I will post pics this afternoon of the boards.. I did see one thing that concerned me on the power board... There 3 are caps right by the the plug that goes over to the mainboard.. The whole board is samwhu caps except a 470uf 10v right by this plug, its a samyoung.. I should have a package in the mail today from digikey and plan on changing that cap for sure.. I will post back with findings and pics if need be after that... If it is determined that the TCon is bad in the OP and my tv, does anyone know if it can be repaired?
Re: 32 samsung lcd will not turn on just blinks 5 times
I think I'm having the same issue as rico and lilmonk. Something on the main board is not providing the BLU_On signal. Did you ever find that service manual Rico?
Re: 32 samsung lcd will not turn on just blinks 5 times
no not yet there was link that i got from samsung in there chat with rep but i did not save the link u have to purchase the cd or paper manual from them i dont know how detailed it will be.
Re: 32 samsung lcd will not turn on just blinks 5 times
there is black small box surface mount looks like fuse or diode says 5v1 as far as i can tell. there is 3.3v one side but no voltage on the other. it is on the main board could this be where my bl-on power is stoping .and if this is diode should it have voltage on both sides.
Re: 32 samsung lcd will not turn on just blinks 5 times
i have the same problem with my 32 tv, and i have copied every test so far that you have done with the same results. just wondering if you could p[ost a pic of that black box you were talking about.. so i can test mine.
thanks
mike
Re: 32 samsung lcd will not turn on just blinks 5 times
I'm having the exact same problems with my LN32B460 (led blinks 5 times, back-light works when the MB is unplugged), but still haven't pinpointed the problem. Maybe this is the service manual you are looking for? http://elektrotanya.com/?q=showresul...oria=&kat2=all
Re: 32 samsung lcd will not turn on just blinks 5 times
i looked at manual already looked at that manual not enough info in it as far as diagrams of boards .still trying to figure it out have not fixed it.as far as black box it was a diode was not problem.seems like a lot people having problems with this tvs more likely main board problem.but i am trying to fix it at component level.if i figure it out i will post results.
Re: 32 samsung lcd will not turn on just blinks 5 times
I'm having the same issue on a thai model LA32B350F1 / bn44-00298b.
Problem lies with PFC IC FAN7530. To do this test, take out RP823 fuse and check if the screen goes on.
But with the RP823 out, normally you should only have 6v - 7v. But here i measure 12.5V which i think is too high and thus the problem will come again.
Anybody knows where i can check to take this voltage down to 6v - 7v.
Anyway : for this issue if you change the FAN7530 AND check also the surrounding diodes, the problem will be solved.
PS : i still need this FAN7530 to test, but as i'm living in laos i cannot order any IC's. if anybody can help me out, please contact me and maybe send it too me by post.
Re: 32 samsung lcd will not turn on just blinks 5 times
When you removed the RP823 (0 Ohm jumper), the PFC IC will no longer get the VCC from QB801's Emitter (QB801 is setup as linear voltage regulator (Emitter follower output), the Base voltage is set to 15.6V, so subtract 15.6V by 0.6V E-B junction voltage of QB801 then the output voltage will be equal to 15V) which mean the PFC Voltage booster circuits will be dead, the output on this pin should be around 15VDC. You should put the jumper back in place and see if you are getting the standby voltage of 13vdc at pin 10/11, and 5.3V at pin 8 of CN802. These voltage should present the minute you plug the power cord into the outlet, it is an always on power supply section.
When you hit the power switch, do you get >3V at PS_ON (PS_ON is from the main board) Pin 1 of CN802.
The DC voltage on that large main DC filter cap should be around 310VDC (220V x 1.414) when the TV is plugged in, and then it should jump up (PFC turns on) to 400VDC when the PS_ON is present.
Notes: QB801 is turn on when Optoisolator PC802S's Opto transistor inside is turn on when LED is turn on by QM802 which is turn on by the PS_ON signal which is applied to the Base of QM802.
The PFC IC FAN7530 requires typical start up voltage for VCC of 12V to operate, and if the voltage is below 8.5V it will go into shutdown mode.
See spec sheet.
Re: 32 samsung lcd will not turn on just blinks 5 times
Did you look at the diagram? The power supply is 15VDC power supply that supplies the voltage to the PFC IC FAN7530 through RP823 so the PFC will run. So why do youi want to bring down that voltage.
Again "The PFC IC FAN7530 requires typical start up voltage for VCC of 12V to operate, and if the voltage is below 8.5V it will go into shutdown mode"
Why do you think it should be 6~7v, please explain the circuits you are looking at.
Re: 32 samsung lcd will not turn on just blinks 5 times
This sounds similar to the problem I am having with the 40 inch version. Have a look at 'Samsung LN40C540 Turns on when it wants to... ' just a page or 2 back. The main board is very similar.
Try cooling the main board in the fridge for 10 minutes or more and then quickly try it.
Re: 32 samsung lcd will not turn on just blinks 5 times
Budm,
I got the 6v-7v from some thai website, but as i checked further more You are right about this 12v. I just changed the FAN7530 but i still got the same problem.
Anything i can do more to fix this ? led still blinks 5 times with no screen. if i take out RP823, i got everything working when the electricity is stable, from the moment i got a powershut, screen falls out. ( here in laos electricity drops 2 - 3 times an hour)
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