samsung LNS4695DX TV Has blinking power light - No Picture

[TubeJunkie]

Hello All.
My Samsung LNS4696DX LCD TV, has no picture or sound. When I push the power button to turn it on, the blue power light blinks. Any common problems with these symptoms? I have the power supply board out, looking for cracked solder joints, and anything out of the norm. Any advise, and all help is greatly appreciated. Thanks,

TubeJunkie

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I assume since it's a Samsung, you've ruled out bad caps?

[budm]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Look at the front and back of the screen in a dark room to see if you notice any glow from the screen.

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

No screen glow at all. I took out all caps (see 1st pic) on power supply board and tested each one out of circuit. None looked bulged, or leaky, but most of the 1000uf 10v caps were at the top 20% of value. Most of these caps drifted down while testing. I ordered these caps last night.

I pluuged in again, after installing the power board, and there is a beeping noise coming from the middle area of this board. Also noticed a blinking green light on the input/tuner board (see pic). Which is labled OP182. Anyone have advise? All help is greatly appreciated. Thanks.

Addition: Also noticed SA801 (looks a lamp/bulb) on power board, is not working. Should this light up?

[TubeJunkie]

Samsung LNS4695DX TV Has blinking power light FIX - SOLUTION

Wow....... Think I figured it out. I took a hair dryer and heated the power board caps (see pic) for about two minutes, turned on the TV, and it worked!!! I'm replacing those caps when they arrive in the mail. I'll let you all know how it goes, after the recap. Hope this helps others. TTYL.

TubeJunkie

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Same problem........... I replaced all the said caps with new Panasonic caps, and still have the same problem. I did'nt replace LM851 & LM852, not sure what they are. Strange looking components... Any advise is welcome.

I can use the hair dryer on the same area, and get it to power on. Should I replace the two big caps (150uf - 450v.)???

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

The LM etc. are inductors and do not need replacement.

Do you get good 13V and 5V from the PSU?

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

The LM etc. are inductors and do not need replacement.

Do you get good 13V and 5V from the PSU?

Hey tomm66,
I'm getting 12.vdc and 5.4vdc. I noticed the big inverter,with the green tape around it (see pic),is humming and sounds like electrical arcing going on. Don't know what this means. What should I do next? Thank You for your help.

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Does it hum when you get it running by heating the PSU?

Can you localise the heating to one specific portion? I know Samsung TVs of this generation had lots of cold joint problems.

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Does it hum when you get it running by heating the PSU?

Can you localise the heating to one specific portion? I know Samsung TVs of this generation had lots of cold joint problems.

Yes, hums while on. And it's humming while it's off, with power cord attatched, of course. I heat the area that I replaced the caps, and it turns on. There is a beeping noise around UB801 too. Not sure what that means. If I let the TV run for a while and turn it off, I can turn on with remote, within a few minutes. But if it cools down, no luck. Any other idea's? Thanks

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Inspect the board around there for bad caps.

There is a voltage regulator on the heatsink for 12V. It derives the voltage from the 13V. Check if that is OK.

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I'll check as you instructed. Can you tell me the number on the board for the voltage regulator? Do you have the schematic for this model?

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I should have said:
"Inspect the board around there for bad JOINTS."

Schematic -- will need "BN44" code printed on board.

Don't recall regulator number sorry.

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I checked all caps, "Out Of Circuit", and most all were pushing, or beyond 20% tolerence. Also, I noticed was, the cheap-o factory caps drift wildly on the meter, as compared to new Panasonic caps.

So, what I did next was to focusing the heating (hair dryer), of the power supply board to small area's. In particular, the two big 150uf - 450v caps. One of those started to swell on it's top and sides, after only a few hair dryer power ups. And intrestingly enough, I could turn it on after 15 minutes. The heat changed the properties of this cap, I think. ??? And it's dying a slow death. Maybe???? Anyway, I ordered all the other caps on the Power supply board, that have yet to be replaced. Still cant find a schematic, guess I'll have to buy one. Wish me luck......

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I replaced all electrolytic capacitors on the power supply board, and it fired right up. Been working great for about a week now. The original CapXon brand caps are total crap. Some of the worst caps ever made. C'mon Samsung. I used all Panasonic capacitors as replacements. And wherever it calls for 10volt, I used 16volt. I read that Samsung was sued for using 10 volt caps in the 12 volt circuit. Oh, I noticed the TV picture is starting to look better and better over the last few days. Maybe the new caps are forming up, or I'm adjusting to a different TV, Oh, Well, Who Knows. I'm happy !!!!!!! Glad I did'nt give up on it.....

Hope this helps others.

TubeJunkie

[budm]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

Great works, I always replace the cap as a set so I do not have to open the TV up again.

[retiredcaps]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

And wherever it calls for 10volt, I used 16volt. I read that Samsung was sued for using 10 volt caps in the 12 volt circuit.

If Samsung used 10V caps on the 12V rail, the caps would have gone almost immediately.

[TubeJunkie]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

If Samsung used 10V caps on the 12V rail, the caps would have gone almost immediately.

I promise you, they used 10v caps in a 12v circuit. Check into it a little more. No disrespect, but that's what was stock, in my TV. And in others too, from what I've read. I dig the explosion avatar..... lol.... Thanks.

[tom66]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I have never seen that in a Samsung. They sure used shoddy caps, but they didn't overvolt them... they would fail within a couple of days to weeks if they were overvolted, not just one month after the warranty ended...

[retiredcaps]

Re: samsung LNS4695DX TV Has blinking power light - No Picture

I promise you, they used 10v caps in a 12v circuit.

Is it possible that 10V caps are actually on the 5.4V or standby rail?