samsung red led flashes 4 times.

[dougc]

Hi, I have a Samsung 26" (le26a457) which very occasionally works ok but most times at switch on the red led flashes 4 times then goes out & set is dead. I have  3.3V & 5V from psu. Any ideas? Thanks, Doug.

[E Parton]

Hi Doug ..
Something in the back of my mind is saying ..dry joints ..
I seem to remember this psu pcb being prone to such things ..
Check around any 'free standing' 3 legged components ...such as Power transistors ..regulators ...and double diodes ..
Also
L1001 2001 and 2002 and C 1039
Good luck ..
Evan

[cheeky2]

Just had the same set in and found very occasionally it would come out of standby(only after removing power source each time), otherwise would flash and go to solid red led. It turns out the brown glue around some of the to92 and q802 transistors and high voltage caps was causing the problem! Must have been changing the capacitance and affecting cct operation.
This is the first time i have found this occur. It took a while to scrape off all the excess off the pcb and had to remove some components encased in the brown glue.
 Nice easy fix :)
 Happy repairing :)

[jordan]

CP-803........150uF/450V

[Turnip]

Hi Cheeky,

First noticed that carbonised rubber glue issue on cheap Chinese tubed portable tellies years ago. Amazed that Samsung ever used it, and to secure stuff that would never move, like small blue HV ceramics and anything else that that ran hot - Sort'a death wish.

Still have a small pile of Sammy power panels where the resultant flash-over killed the board - you were fortunate, as none seem to turn up cheap on the Flea - And we can guess why.

Happy scraping - Chris.