Samsung ccfl tv powerboard clicks every 5 seconds.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Well… that would have been a nice find. Lol

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Btw. Congrats to your 10k posts!

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

The resistor vid was a nice find, but I am afraid, that this TV doesn’t have any resistance like that on the PFC VCC pin.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, looking straight at ICM801, the first pin on the inside has 384 volts, the middle pin on outside is 14.78 volts, I couldn't get to the middle back pin without touching the other front pins together with it so I didn't check that one.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Thanks, I guess I had a few quality posts along the way, wasted a lot of energy arguing with sad people, ignore button works for those types, if they get no response they will give up. I like helping more than working on my own junk, I don't know why but it seems easier to see whats wrong with with everything else but my own.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Check pin 4. If it has more than 6v the protection is on and she shuts down. If you are below that 6v threshold, I am calling this pwm fubar.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Maybe solder a small piece of wire to it.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, can you tell which pin is 4? I think I'll need to get a microscope to see the numbers on that chip to look it up.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, I'll try the wire, I could reach all but the middle back pin, unless that one isn't #4.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Thanks, I guess I had a few quality posts along the way, wasted a lot of energy arguing with sad people, ignore button works for those types, if they get no response they will give up. I like helping more than working on my own junk, I don't know why but it seems easier to see whats wrong with with everything else but my own.

I hear ya, same here. I gave up on that too and making sure not to go down the spiral. Not worth my time, as I am very limited these days.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, I'll try the wire, I could reach all but the middle back pin, unless that one isn't #4.

Look at the spec sheet. Pin one is the outer most and a bit separated pin.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

And yes, I think the back middle pin as you call it is the one… maybe tap it somewhere else of the board.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

I guess I could switch it out with the one on original board, I'll give it a shot, Thanks.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Easy to pick off the opto PCM801 pin 4. There is also a zener and a diode you could pick it from. Gonna hit the sack. Catch up again tomorrow.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

I'll try it upside down.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Thanks, soldered a wire on, it's 15.5 and steady.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, thanks a lot, I think there's hope for this one, glad I have the extra board for comparison and spare parts.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

My bet is that on the optocouplers PCM801 and PCM802 the DCV on pin 1 and pin 2 compacted to secondary GND is nothing there. If there is nothing there, or the voltages are about the same, the opto is off and the FB pin 4 on the ICM801 PWM goes high and goes into overload protection and shuts down.
You got to find that short!
I suppose you could do something with the FB pin, not allowing the IC going into shut down. However I really don’t recommend that, as things get a bit unpredictable and the PWM wants to go full bore.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, Thanks, I didn't know what those optos should measure, I tested them neg probe to hot ground, PCM801, pin 1 is 1.8v slightly fluctuating, pin 2 is 1.4v lightly flux, pin 3 is 0 volts, pin 4 is 14.6v. PCM802, pin 1 is 1.3v, pin 2 is 1.4v, pin 3 is 14v, pin 4 is 15v, looks like all the ones with the lower voltages like 1.3, 1.4 start about 1.8 or so then work down to 1.3 and stop. Did tests with powerboard jumped as stand alone. I guess the measurements from 1 and 2 to hot ground aren't helpful, I just tried them all while I was on hot ground, lol.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok my bad, I'll get the 1 and 2 pins measured to secondary/cold ground, ok only showing millivolts when using chassis ground for pins 1 and 2 of both optos.