Samsung LE32A336 bad PSU (maybe)

[hydex]

TV: Samsung LE32A336
PSU: BN44-00213A

Hi!
Have to say first that i'm a newbie and have been fixing electronics very randomly.
My friend gave me this tv to see if it could be repaired with low cost. I have measured every thing from the psu board that I could imagine would be a problem but found zero faults.
Symptoms are that when tv is on standby (red light on) I press power button it starts to blink red light 5 times and makes this sound from cap CM810.
There no picture or anything. If I don't cut the power it will go like this forever.

Any ideas what to look for ? Could that capacitor CM810 be BAD or is this sound a symptom that is caused by something else ?

Thanks!

[hydex]

Re: Samsung LE32A336 bad PSU (maybe)

And of course i forgot to attach the sound file to previous message. I can't seem to find EDIT button anywhere so I'll upload the file here.
Sound quality is not very good.

[hydex]

Re: Samsung LE32A336 bad PSU (maybe)

Any suggestions where to look ? =(

[selldoor]

Re: Samsung LE32A336 bad PSU (maybe)

Hi - looks like no-one knows or your thread gets missed- perhaps due to time differences. Anyway I know very little about tvs but if we get some dialogue going others may join in. I am assuming you have a multimeter and soldering equipment?
As you have not given the actual results of any of the tests you have done I will just ignore them.
As you seem to have the manual does it say what the flash code means?.
Are you sure the sound is from the cap ( Is it the small blue ceramic one and have you taken some glue off it?) If you have check it is not physically damaged - ceramic cracked on the legs?
Could the sound be from the transistor on the heatsink nearby?
Did the fault just start or was it brought on by an event - power cut lightening strike.

[budm]

Re: Samsung LE32A336 bad PSU (maybe)

That cap 2.2nF (0.0022UF) 1000V, is a filter cap to take care of the high frequency generating by the two MOSFET swtiching circuit for the 24vdc power supply for the backlghts inverter.
Remove the cable between the inverter board and the power supply board and see if you can get the TV to come on.
Do you also have about 390~400vdc (when TV is off it should have about 325V, when TV is on it should have 390~400vdc (pfc kicks on)) on that large DC filter cap C803?
Be careful since you are working in the HOT PRIMARY side of the circuits.

[Napalm]

Re: Samsung LE32A336 bad PSU (maybe)

Hello.
I have one of this lcd that shuts down after about an hour working fine. after shutdown it tries to power on again, show's picture for about a second then off again repeatedly.

I open it up, capacitors look fine to me.
The psu model is BN44-00252A

What can I do to repair this?

thanks.

[selldoor]

Re: Samsung LE32A336 bad PSU (maybe)

Post good clear pictures of your boards - different to OP.

Does it go off quicker if you warm it with a hair dryer?
Does it stay on longer if you cool it with a fan?

[budm]

Re: Samsung LE32A336 bad PSU (maybe)

May be start a new thread with Samsung TV mode???l and power supply model BN44-00252A.
http://www.shopjimmy.com/samsung-bn4...wer-supply.htm
TV model?
LN32A330?

[anotherdude]

Re: Samsung LE32A336 bad PSU (maybe)

Hello.
I have one of this lcd that shuts down after about an hour working fine. after shutdown it tries to power on again, show's picture for about a second then off again repeatedly.

I open it up, capacitors look fine to me.
The psu model is BN44-00252A

What can I do to repair this?

thanks.

sounds exactly the same as i've just had

does it reboot endlessly?

when the fault occurs heat up the main board near the shielded area with a hair dryer

[Napalm]

Re: Samsung LE32A336 bad PSU (maybe)

Yes it rebooted endlessly.

I called a friend and he identified what must be the problem: dry joints

When the tv heats the solder no longer makes good connection and goes out.

here are some pictures. tested the tv for 4,5 hours and still on...

[selldoor]

Re: Samsung LE32A336 bad PSU (maybe)

Remember if you are testing with the back off it wont get as hot as with it on.

[Napalm]

Re: Samsung LE32A336 bad PSU (maybe)

Ok I tested it before without the back on.
Now I put the back, and it is working so far for 2 hours...