Samsung LNT4061 Got power and sound but no backlight

[Scuba]

Hey I was watching this tv and adjusting color settings when I hear a pop and now I have no backlight but sound still works....I can see the screen if I use a flashlight and the power stays on just no picture...I thought maybe the backlight board but I came here to ask the experts.I see no physical signs that any of the capacitors bulged out but Ill post pics.

[tom66]

Re: Samsung LNT4061 Got power and sound but no backlight

If you heard a "pop" I'd check that little red fuse in the inverter section of the power board.

[Scuba]

Re: Samsung LNT4061 Got power and sound but no backlight

Are you referring to this?? If so I checked it and there is no continuity...Can I just jump it to test TV? Or Can I just permanately put a jumper there? TIA

[tom66]

Re: Samsung LNT4061 Got power and sound but no backlight

Doing such a thing is likely to result in further damage to the board. The fuse is there for a very good reason. You need to look at why the fuse blew. I'd check the components on nearby heatsinks for burn marks / obvious damage.

[Scuba]

Re: Samsung LNT4061 Got power and sound but no backlight

Thanks for the help I ordered a refurb power board as I cant see any physical signs of burns anywhere and Im not very good at checking capacitors and stuff After I get the board in I will check back with progress

[Scuba]

Re: Samsung LNT4061 Got power and sound but no backlight

Well the new board will be here tomorrow but I still want to find out what went wrong on this one...The only thing I can see as far as maybe physical damage is in the following picture...It looks a little wet on the left side for some reason..Does that mean its leaking and bad? And does anyone know what voltages are supposed to come out of that piece so I can check to see if it is bad?

[tom66]

Re: Samsung LNT4061 Got power and sound but no backlight

Approx 3,500V. Attempting to measure the output will destroy a multimeter, so it is not recommended.

[Scuba]

Re: Samsung LNT4061 Got power and sound but no backlight

Approx 3,500V. Attempting to measure the output will destroy a multimeter, so it is not recommended.

Thanks for all your help Tom66 and the heads up on the 3,500v before I destroyed my multimeter
I got the new power board today and the TV is fixed now...I am using it as my computer monitor right now and its great
I may try and tackle an old 40' Polaroid LCD next

[rlega]

Re: Samsung LNT4061 Got power and sound but no backlight

Hello,

This is an old post, but I wanted to contribute with some personal pictures in case someone come across the same problem as I had. The TV is Samsung LNT4061FX/XAA and the problem was, as soon as you connect power to it, you would hear a click from the power supply, the red light flashes 5x, then off, then you would hear the same click from the power supply, the red light flashes 5x, then off, and the cycle continues like three more times until finally the TV would turn on. The problem was the capacitors on the power supply, four of them were bulged (1000uf 10v).

[jrg_21]

Re: Samsung LNT4061 Got power and sound but no backlight

Is this thread being monitored any more? I have a very similar issue with my Samsung LNT4061, except I don't have the cycling issue or a faint picture. I have sound but NO picture at all, not even with a flashlight. The TV will appear to be powering on (it does the Samsung "noise/notes" upon pushing the on/off button) and I think it is, just no picture at all.

I have replaced the inverter board ($12 off eBay) and replaced the 5 capacitors I have read cause problems for other people (2 2200, 10v and 3 1000, 25v). But I did not notice any bulging capacitors; I just did this because it was a common way for these TVs to be fixed.

I am a novice with this type of stuff so I might not be familiar with all terminology. But I'll research whatever I can on the TV to answer questions about possible solutions.

[nomoresonys]

Re: Samsung LNT4061 Got power and sound but no backlight

Is this thread being monitored any more? I have a very similar issue with my Samsung LNT4061, except I don't have the cycling issue or a faint picture. I have sound but NO picture at all, not even with a flashlight. The TV will appear to be powering on (it does the Samsung "noise/notes" upon pushing the on/off button) and I think it is, just no picture at all.

I have replaced the inverter board ($12 off eBay) and replaced the 5 capacitors I have read cause problems for other people (2 2200, 10v and 3 1000, 25v). But I did not notice any bulging capacitors; I just did this because it was a common way for these TVs to be fixed.

I am a novice with this type of stuff so I might not be familiar with all terminology. But I'll research whatever I can on the TV to answer questions about possible solutions.

be careful working with power supply, HIGH VOLTAGE, on primary side, can be deadly, I'd check for expected voltages coming from power supply, should be a legend of expected voltages beside pins where connectors go.

[rlega]

Re: Samsung LNT4061 Got power and sound but no backlight

Is this thread being monitored any more? I have a very similar issue with my Samsung LNT4061, except I don't have the cycling issue or a faint picture. I have sound but NO picture at all, not even with a flashlight. The TV will appear to be powering on (it does the Samsung "noise/notes" upon pushing the on/off button) and I think it is, just no picture at all.

I have replaced the inverter board ($12 off eBay) and replaced the 5 capacitors I have read cause problems for other people (2 2200, 10v and 3 1000, 25v). But I did not notice any bulging capacitors; I just did this because it was a common way for these TVs to be fixed.

I am a novice with this type of stuff so I might not be familiar with all terminology. But I'll research whatever I can on the TV to answer questions about possible solutions.

hello jrg_21,

Could you please post a clear picture of the power supply and a close up of the 5 capacitors that you replaced?

If I remember correctly, there are (3) 47uf capacitors.

Check this post from budm concerning LNT4061 TV.

Thanks

[jrg_21]

Re: Samsung LNT4061 Got power and sound but no backlight

I attached pictures of the board with the newly installed capacitors (2 pics of those). I also attached pictures of the old capacitors. As I said, I didn't see any visible signs of bulging but went ahead and replaced anyway because it was such a common solution.

Thanks for any feedback.

*I just read budm's post and saw the pics. I can make my pictures much better now that I've seen some good examples. Do you think I should definitely replace the 3 47uf capacitors before I get too much further?

[nomoresonys]

Re: Samsung LNT4061 Got power and sound but no backlight

hello jrg_21,

Could you please post a clear picture of the power supply and a close up of the 5 capacitors that you replaced?

If I remember correctly, there are (3) 47uf capacitors.

Check this post from budm concerning LNT4061 TV.

Thanks

you may have gotten a bad inverter from ebay, hard to tell.

[nomoresonys]

Re: Samsung LNT4061 Got power and sound but no backlight

Is this thread being monitored any more? I have a very similar issue with my Samsung LNT4061, except I don't have the cycling issue or a faint picture. I have sound but NO picture at all, not even with a flashlight. The TV will appear to be powering on (it does the Samsung "noise/notes" upon pushing the on/off button) and I think it is, just no picture at all.

I have replaced the inverter board ($12 off eBay) and replaced the 5 capacitors I have read cause problems for other people (2 2200, 10v and 3 1000, 25v). But I did not notice any bulging capacitors; I just did this because it was a common way for these TVs to be fixed.

I am a novice with this type of stuff so I might not be familiar with all terminology. But I'll research whatever I can on the TV to answer questions about possible solutions.

look the tcon board over real good, check anything labeled F, F=fuse, there may be more than one.

[jrg_21]

Re: Samsung LNT4061 Got power and sound but no backlight

thanks for the replies. not sure how to tell if inverter board from ebay is bad. and not sure what exactly to look for on tcon board, but i'm posting pics of it in case you would like to see it.

i replaced the 3 47uf 50v capacitors and it did not fix it. at this point, i've reached my limit (actually i reached my limit as i was unscrewing the back!) unless there are additional things I should look for. i'm not opposed to spending a little $ to get new components/boards because it seems like a shame to have this tv go to waste. any suggestions on next steps are much appreciated.

and, once again, thanks for all the replies so far!

[jrg_21]

Re: Samsung LNT4061 Got power and sound but no backlight

As I'm sure it may be interest to the group, I was able to find out from a local electronics expert that my issue is a bad 12v regulator chip (IC). But unfortunately when he made the fix, the screen turned out to have a crack so no picture. I guess when I was moving it around to fix it, I must have bumped it or set it down wrong. Although I thought I was careful.

Thanks For the help. I appreciate it.

[rlega]

Re: Samsung LNT4061 Got power and sound but no backlight

As I'm sure it may be interest to the group, I was able to find out from a local electronics expert that my issue is a bad 12v regulator chip (IC). But unfortunately when he made the fix, the screen turned out to have a crack so no picture. I guess when I was moving it around to fix it, I must have bumped it or set it down wrong. Although I thought I was careful.

Thanks For the help. I appreciate it.

Wow, that really sucks.

You welcome!