Samsung 55" lcd ln66c630 no backlight

[Tdbueche1]

Was watching tv, heard a small pop and picture went out while sound still works. Ordered and replaced inverter board but still have the same issue. Given the pop sound is it likely that one of the ccfl bulbs is bad and causing the entire issue? I have no light at all from the tv other than the power lcd light. Thought of trying a new tcon board but not sure. All caps look good and still have power/sound so thing the main board should be good to go.

I know getting to the ccfl's is not going to be easy so wanted to get opinions before starting that. Tcon board would be easy but the pop then no picture makes me wonder if that is even the issue.

[budm]

Re: Samsung 55" lcd ln66c630 no backlight

Can you please verify the model number?

[Tdbueche1]

Re: Samsung 55" lcd ln66c630 no backlight

Model is LN55C630K1F. Sorry about that.

[Tdbueche1]

Re: Samsung 55" lcd ln55C630 no backlight

This is the correct model #

[budm]

Re: Samsung 55" lcd ln66c630 no backlight

OK, your TV uses power supply-inverter board and balancer board that gets the High Voltage outputs from the Power supply-inverter board and get distributed to each lamps.
If one of the lamp is bad you still should see the backlights flash on for seconds before the inverter goes into shutdown due to bad lamp (the inverter will fire up the lamps first, if it detect too much current flowing in any one of the lamp the little lamp current sensing transformers on the balancer board will send the feedback signal to tell the inverter to go into shutdown, or if it detects that after the lamps are fired up but one or more lamp did not stay on, it will also go into shutdown. The detection will detect the problem in the first 3 seconds to make sure all are OK for the inverter to stay on.
So look real close at the screen in the dark room to see if the lamps flash at all first.

[Tdbueche1]

Re: Samsung 55" lcd ln66c630 no backlight

Thanks! Tried that and the screen stays completely black. Back cover is off so tried also looking for some sign of light from the back of the unit and nothing there either. Does this point us in any sort of direction?

[budm]

Re: Samsung 55" lcd ln66c630 no backlight

That means the Inverter circuits ddi not even try to run.
So next thing we need are really GOOD CLEAR FOCUSED pictures of the back side of the TV so we can see how all the boards are connected together, and then good pictures of the power supply board.

[southernmd2]

Re: Samsung 55" lcd ln66c630 no backlight

I too am have this same issue with this model. replaced the inverter with no change. I read that c1818 on the power supply board had been the fix for others with this problem. but upon inspection found the location for c1818 but no capacitor.