Samsung LNS3241 no picture, scattered multicolor lines

[Kelly C]

I have a problem with a Samsung LCD TV LNS3241. Current condition: dark screen, backlight on, several multicolored lines, no menu. Utilizing the info in this marvelous forum, I have already replaced four capacitors on the upper right of the power board which is BN96-03057A. The tv now powers up much more quickly, but the picture is unchanged. Any help greatly appreciated.

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Can you show a picture of the fault?

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

There is no change across inputs.

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

OK, can you provide a picture of the back of the set, cover removed?

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Here it is.

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

OK, the top most board, can you get a closer picture of it? Try to get as best focus as possible with minimal glare.

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

The t-con, correct?

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

I've highlighted some parts on the t-con.

For each part, please note down the reference code (IC### or U###), the part number (e.g. LD1117-29), and test the DC voltage on each pin, with reference to chassis ground.

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Readings from analog meter.
Wide tabs match middle of three.

From the left:

UP4
L1117DG
2.2
4.0 (top to bottom)
5.8

U14
MMC6100B
0
1 (top to bottom)
5.8

UP2
059I4
5.8
3.8 (L to R)
0

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

I suspect MMC6100B to be your fault, it is a common problem on these T-cons, though I am not certain about the others. Can you verify #1 and #2? Also, any other digits printed on those regulators, below the main part #?

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Went to 2.5V scale, same readings.

NIKOS
L1117DG
QA5C11F16

MMC6100B
25 F16B

AK33P
059I4

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Uh, do you happen to be using an analog multimeter? A digital one is preferred, as an analog meter simply doesn't have sufficient accuracy or resolution.

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Sorry, that is all that I currently own.

I have a few defunct boards, but I doubt I can match that part. Looks like that single regulator would be a significant fraction of the cost of a t-con board.

[tom66]

Re: Samsung LNS3241 no picture, scattered multicolor lines

Replacing the T-con might fix your problem, but without checking the voltages accurately, no way to be certain.

[Kelly C]

Re: Samsung LNS3241 no picture, scattered multicolor lines

T-con fixed it. Thank you for your help!