Samsung LN40A550P3FXZA screen goes BLACK

[twilliard]

Samsung LN40A550P3FXZA

TV seems to be working ok, Good picture and sound

Then this problem occurs:

Sometimes when changing channels, The TV screen goes BLACK /with sound and does not show picture nor can you see the Menu

Checked capacitors no signs of bulging

Any ideas what to start checking

Thank You

[tom66]

Re: Samsung LN40A550P3FXZA screen goes BLACK

Check if the backlight goes out. You can check if the lighting visible from the back of the set goes off, or if the screen loses its slight glow. If there is still a glow from the screen, it's probably T-con/Main/Panel related, if it doesn't glow, it's probably PSU/Backlight related.

[twilliard]

Re: Samsung LN40A550P3FXZA screen goes BLACK

Now No picture

No Backlight

still have sound

??

[caphair]

Re: Samsung LN40A550P3FXZA screen goes BLACK

How old is the tv? I'd suspect caps, even if they didn't look bulged they could be bad. Take some voltage measurements

[johnboy1313]

Re: Samsung LN40A550P3FXZA screen goes BLACK

It's likely one of the transformers on the power supply/inverter board. Post pictures of your power supply.

[johnboy1313]

Re: Samsung LN40A550P3FXZA screen goes BLACK

Error

[TechOp]

Re: Samsung LN40A550P3FXZA screen goes BLACK

I agree with johnboy and I think I have some parts for this model.

[twilliard]

Re: Samsung LN40A550P3FXZA screen goes BLACK

I replaced the power supply/inverter board, I think it was the transformer on the power Board

Thanks for all of the responses!!

[TechOp]

Re: Samsung LN40A550P3FXZA screen goes BLACK

I have replaced a few transformers on inverters. Now I scrap one board to use parts off it to fix the others.

"The Needs of the many out weigh the needs of the few or the one"