L65X1Q_DHS / BN44-00627A Samsung UN65F6400AF Standby blinks twice five times

[Donny2derby]

Re: L65X1Q_DHS / BN44-00627A Samsung UN65F6400AF Standby blinks twice five times

What a way to end it!

I can’t believe you would stop! You’ve got 3 or 4 very knowledgeable and smart blokes basically spoon feeding you how to go about repairing the set and you’ve give up!

What a tit!

[IoT-Maker]

Re: L65X1Q_DHS / BN44-00627A Samsung UN65F6400AF Standby blinks twice five times

@Davi.p thanks for your hint.

I never had a bad transformer on a PSU. Got this BN44-00627A here since March and could not fix it. First i found the D2011K damaged. The IC is next to the transformer. Also one UF4007G diode was damaged. I replaced it with a UF4007 only to find out weeks later it's causing trouble. The boost circuit was not working. It needs 390V but was only at around 316-320V. I replaced the UF4007 with the (hard to find) UF4007G which is much quicker and the boost voltage works.

But there was still a clicking and no stable output voltage. Because i could not find the fault, i bought a working board to compare measurements. Some values were different but not that much. At the end, i started to swap parts. I swapped all elkos, all diodes on the top side. Nothing helped.

Finally, because i read this post today and the transformer on the old board was heating up a little bit (which the one on the working board did not), i desoldered the 210064HD KE-03B DY transformer (something i did never before) and testet it with a DE-5000. One winding should have 0,410 Ohm but i read 1,230 Ohm. I swapped the transformer and the board was working as expected. No clicking, stable voltage.