Re: Samsung LE40D550K1W no backlight

Problem solved.
Since replacing UI801 didn't fix my problem I started checking the diodes and z-diodes around it.
Sure enough one of the zeners was broken. ZDI805 a 6.8V zener had a breakdown voltage of ~4.5V.
Replaced it and now everything works.

Re: Samsung LE40D550K1W no backlight

Well I'm back at the beginning.
Replacing the SEM2106 changed nothing.
If anybody has any ideas I'm all ear.

Re: Samsung LE40D550K1W no backlight

Hi luisparada, sorry for the late reply...
I just took a look at CP811 and on my board the value is 220pF ±10%/1kV, if I decoded the markings correctly. The complete marking is "LB 221K 1KV".
At the moment I'm still waiting for the ICs to arrive (had some trouble with a seller on Alibaba).
I'll post results when they get here (in one or two weeks).

TV starts up, shows picture (checked with flashlight) and plays sound but the backlight doesn't come on. Very seldom the backlight flickers for a few seconds (usually a few minutes after being powered on).

[B]Part #[/B] (Haven't found any matching datasheets so far.)
PSU: BN44-00440A
MainBoard: BN41-01751
Inverter: SST400_12A01 INV40T12A

What i did so far:

1) Visually checked all electrolytic capacitors. They looked fine but i replaced them anyway, except the big main caps.

2) Checked for cold solder joints.
...

Re: New Members - please post your introductions here

Hello there. Have been lurking on BadCaps for quite some time but now have a problem that I need help with.