Samsung ccfl tv powerboard clicks every 5 seconds.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Wonder if one or both of those optos are bad, I could switch them out, not sure how to test them in circuit but I can test them out of circuit with a resistor and 2 meters.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

They aren’t bad. There is no voltage going there to light up the lil led inside. Same if the voltages are kind of equal.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Ok, Thanks, was just checking ICS801 and pin 8 is ground and beeps back to primary ground/showing continuity as normal but pin 3 which is CS is also beeping back to primary ground, I think that is bad, both chips on both boards do it, I'm thinking they are both bad but not sure, the chip is there: https://www.google.com/search?client...bV3SosWCiznwRM

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Guess I could be wrong, just checked another powerboard which is not the same board but similar and it shows continuity from primary ground to pins 1 and 3.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Traced it back and it looks like it does go to negative filter cap leg thru a resistor.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

ICS801 pin 8 GND is tied to the main filter cap GND. I don't see any resistor you are talking about in the schematic.
CS pin 3 goes through a resistor to GND and that is supposed to be like that.

you really need to look at the PWM's data sheet. It will tell you what to expect on which pin and how for example the soft start works, how it starts and when it will shut down

Something like this is hard to diagnose and twice as hard for me not sitting in front of it.

Maybe do something like a sheet up and write down what you absolutely know, like boosted voltage, PWM chip, then the pins and pin names followed by the voltages on each pin etc.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

I'm probably not seeing something right, it looks like it runs thru RS803, CS803 and works down to neg. filter lead.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

https://www.shopjimmy.com/samsung-bn...w-605563813499

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

For sure, remote troubleshooting is tough, I'll look at the sheet for ICS801 again and measure those pins on standby and when jumped, maybe a clue will come, Thanks.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Giving up on this one, Thanks for helping, this old heavy relic just isn't worth all the effort, from what I read about this model it was kind of a lemon from the start, Thanks again.

[CapLeaker]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

i guess we had at least a little fun!

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

For sure, I think I learned something, now if I could get my brain to remember what I learned, seems to go in and leak out a day or a week later lol, damn memory, reminds me of that movie with Drew Barrymore and Adam Sandler, where he has to play a video tape for her every morning because she can't remember what happened or what she learned yesterday.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Hello, I have a quick question, got this ch341a mini black to mess around with, have a suspect eeprom, wondering what is procedure. Do I need to try to freeze the eeprom before reading or just first try reading, can this thing fix a corrupt eeprom, I think it can or is it necessary to get a new one and try to program it? Thanks.

[nomoresonys]

Re: Samsung ccfl tv powerboard clicks every 5 seconds.

Will try to look it up, was just wondering about best practice for procedure.