Samsung 2693HM white screen

[xscp]

Hi.

I have a Samsung 2693HM that only displays a white screen when it's turned on.

I took it apart and reseated the cables and it worked fine for a day or two, but then it came back. Reseating the cables don't seem to help anymore.

I would like to try to fix it, or at least diagnose the problem to see if it's worth getting parts for it.

I have no experience with electronics, I have access to a simple multimeter and can do basic soldering if needed.

Any help would be appreciated.

[selldoor]

Re: Samsung 2693HM white screen

Pictures are really good apart from the first one - can you re take it.
In Pic 5 right in the middle at the top below the connector ther is a small white fuse that looks to sat ?T 3A on it - can you test it.
No power to the board meter on ohms 200 one probe to each side

[xscp]

Re: Samsung 2693HM white screen

I tested the fuse and the reading was going down from around 10 to 0.

Also, when i move the main board it makes strange sounds, like if some small metal object would move around inside, i can't really locate where it comes from.

[selldoor]

Re: Samsung 2693HM white screen

The ohms reading should not fall away - have you good battery in meter?
Result should be the same as touching probes together.
"Also, when i move the main board it makes strange sounds, like if some small metal object would move around inside, i can't really locate where it comes from."
That is exactly what it is - I think it is the rectangular component to the right of the main processor. cant make it out - perhaps 530s or something.
The screen can be turned from landscape to portrait and the little ball switches the picture.

Suggest you read these to threads if you have not done already
https://www.badcaps.net/forum/showth...ghlight=2693HM

https://www.badcaps.net/forum/showth...ghlight=2693HM

[xscp]

Re: Samsung 2693HM white screen

I think I had the meter on wrong settings or something, I checked again and now it was 0 for both the fuse and the probes touched together.

My t-con seems to be different than the one in the other thread. I followed what momaka wrote and measured VDDA, VEEG and VDDG, they were 5K, 41.9K and 99.8K in that order. I will measure the capacitors and voltages tomorrow.

Are the highlighted components the ones he mentioned (D502, Q503, and Q504, and D504)? The labels are a bit cluttered.

[selldoor]

Re: Samsung 2693HM white screen

Yes I think they are - it is not too critical as he is not testing those he says to test the
capacitors part numbers C??? in the area around them - they are the buff/brown ones.
Maybe as it is a slightly different board the caps may be better.

Next time the board is in the machine can you try to remember to test the voltage on each side of the fuse with respect to ground.
Hopefully Momaka will join in when you have the voltage tests and tell us what he thinks.

[xscp]

Re: Samsung 2693HM white screen

The capacitors on the t-con seem fine, none of them had low resistance. The lowest was around 0.4K iirc.

Both side of the fuse was 5.27V. VDDA, VDDG and VEEG were all 0.

I checked the voltages on the psu at the connectors (5.3V / 18V / 24V) and they were ok.

[selldoor]

Re: Samsung 2693HM white screen

Cant actually see the fuse? anyway can you test the voltage regulators - left hand side of the board one is a1117 18 the other ends in 33

[xscp]

Re: Samsung 2693HM white screen

I meant the fuse on the main board.

I tested the voltage regulators (the outer pins to the middle/ground, right?), 17-18 was 0 / 0.1-0.6V, 33 was 0 / 0.6-0.8V

[budm]

Re: Samsung 2693HM white screen

Please report in this format:
Big tab up, Black probe on chassis.
Left (1, GND)) = xxx V
Middle (2, or tab, output) = xxx V
Right (3, input) = xxx V

[selldoor]

Re: Samsung 2693HM white screen

Wrong - If you re doing a voltage test then black probe to chassis ground
and probe each pin, meter on vDC20

[xscp]

Re: Samsung 2693HM white screen

J384 1117-18
Left = 0 V
Middle = 0 V
Right = 0.45 V - 0.75 V

J164 G1084-33
Left = 0 V
Middle = 0.45 V - 0.75 V
Right = 0.85 V - 1.05 V

The voltages were jumping up and down.

[budm]

Re: Samsung 2693HM white screen

For the light of me, I cannot see the fuse on the T-CON board, I expect it to be close to the right side of the LVDS connector.

[mmartell]

Re: Samsung 2693HM white screen

It *may* be on the left side of the lvds connector, on the top right of the barcode sticker labelled "FU10" but hard to tell.

[mmartell]

Re: Samsung 2693HM white screen

Here..

[xscp]

Re: Samsung 2693HM white screen

Is that a fuse? I can't make a better picture at the moment, it has UD written on it if that helps.

Its resistance was 100 ohm (at first), voltages were 5.28V and 1.04V, with the latter jumping down to 0.8-0.9V and occasionally to 0V. When i checked the resistance again it was 245 ohm.

[mmartell]

Re: Samsung 2693HM white screen

Ya I can't be sure and I'm not familiar with that marking either.

[retiredcaps]

Re: Samsung 2693HM white screen

A good fuse should measure less than 1.0 ohms.

UD code suggests 3.15A 24V as per

https://cdn.badcaps-static.com/pdfs/...7263e74802.pdf

[budm]

Re: Samsung 2693HM white screen

The capacitors on the t-con seem fine, none of them had low resistance. The lowest was around 0.4K iirc.

Both side of the fuse was 5.27V. VDDA, VDDG and VEEG were all 0.

I checked the voltages on the psu at the connectors (5.3V / 18V / 24V) and they were ok.

Is that a fuse? I can't make a better picture at the moment, it has UD written on it if that helps.

Its resistance was 100 ohm (at first), voltages were 5.28V and 1.04V, with the latter jumping down to 0.8-0.9V and occasionally to 0V. When i checked the resistance again it was 245 ohm.

That is why I am confused because you indicated that it has 5.27V on both ends of the fuse but the regulators show almost nothing.
So which FUSE did you test on the T-CON to get that 5.27V on both ends and now you have 5.28V on one end and 1.04V on the other end?

[xscp]

Re: Samsung 2693HM white screen

Next time the board is in the machine can you try to remember to test the voltage on each side of the fuse with respect to ground.

I thought he meant the fuse on the main board (picture 5), because that's what he mentioned in post 2. This one had 0 resistance and 5.27V on both sides.

In my last post I wrote about the one on the t-con, the one pointed out by mmartell, this had 100 / 245 ohm resistance and 5.28V and 1.04V on its ends.