Samsung 910t

[IRShifty]

Purchased this monitor to fix. I cant seem to find the problem. I haven't done a lot of repairs that have to do with the video. When powered on the back lights come on and it has an image in the top left that flashes between the words digital and analog as if it is searching for signal. That goes on for about 10 sec and then it goes black and then the screen is populated with colored vertical lines. I don't have it apart right now but I have opened it and reseated the ribbon cables and all the caps look visually good. I believe the cap brand is Samxon. I am really lost on this one so any ideas are appreciated.

[PlainBill]

Re: Samsung 910t

Did you have it hooked up to a working computer? If so, and based in part on the 'colored vertical lines', I would suspect a problem on the logic card.

Have you checked the power supply voltages? It bears repeating: Even the poorest Chinese cap maker has learned to make capacitors that don't look bad when they fail.

PlainBill

[IRShifty]

Re: Samsung 910t

I did have it hooked up to a working computer, but it displays the same problem with no video hooked into it. Where do I check for power supply voltage and what am I looking for?

[EGuevarae]

Re: Samsung 910t

I did have it hooked up to a working computer, but it displays the same problem with no video hooked into it. Where do I check for power supply voltage and what am I looking for?

I agree with PlainBill on the VBoard problem. As I have no prior knowledge of that specific model, a pic would help. That way we can tell you were to check for voltage readings.
Eduardo

[IRShifty]

Re: Samsung 910t

Here are some pictures.

[EGuevarae]

Re: Samsung 910t

Here are some pictures.

Check the voltage readings on the lower left connector of first pic. Sometimes (very often) the pins are labeled (5v, GND, etc). Also, check the ribbon that goes to the panel from the vboard.

[lucky13]

Re: Samsung 910t

When powered on the back lights come on and it has an image in the top left that flashes between the words digital and analog as if it is searching for signal. That goes on for about 10 sec and then it goes black and then the screen is populated with colored vertical lines.

That's the standard Samsung signal detection routine. If it doesn't think there is a signal Analog or Digital, it will keep showing that.

So, that means your inverter board is good and your LCD works.

My guess is there is something wrong on the logic/main board (the green one).

If the voltages are there, then there is not a whole lot more you can do except get the same board elsewhere.

Do follow the instructions eguevarae provided you. Good luck.

[EGuevarae]

Re: Samsung 910t

That's the standard Samsung signal detection routine. If it doesn't think there is a signal Analog or Digital, it will keep showing that.

So, that means your inverter board is good and your LCD works.

My guess is there is something wrong on the logic/main board (the green one).

If the voltages are there, then there is not a whole lot more you can do except get the same board elsewhere.

Do follow the instructions eguevarae provided you. Good luck.

I have a 940T that does something similar. It scans for signal and if it does not find it, it goes into standby; but if it does, it displays an image but at the right of the screen there's a band of like an inch and a half of colored lines. Seeing my notes, it was reduced at like 4~5 lines by pressing the top part of the panel, where the flex cables go from the board at the back of the panel to the TFT/LCD screen itself. What model of LCD panel does your 910T use?

[IRShifty]

Re: Samsung 910t

mj19bs

[EGuevarae]

Re: Samsung 910t

mj19bs

?

[Wizard]

Re: Samsung 910t

that's model code (samsung have 2 lines of models on sticker).

What is asked about is brand & model of the *internal* LCD PANEL.

Cheers, Wizard

[EGuevarae]

Re: Samsung 910t

that's model code (samsung have 2 lines of models on sticker).

What is asked about is brand & model of the *internal* LCD PANEL.

Cheers, Wizard

Exactly!.
Look at the pic IRShifty, it is from the panel of a 730B. That's what I'm asking

[IRShifty]

Re: Samsung 910t

[EGuevarae]

Re: Samsung 910t

I must have a screen like that. Let me see if I can locate it. If I find it, it must be with its VBoard. If found, I'll see if I can send you the VBoard.
What about the Voltage readings. Did you check those?

[IRShifty]

Re: Samsung 910t

I will not hesitate to pay shipping, I checked the voltage but I was getting some odd readings. What should I get?

[EGuevarae]

Re: Samsung 910t

I will not hesitate to pay shipping, I checked the voltage but I was getting some odd readings. What should I get?

You must have 5v and 13v. One line will show you 5v with signal and 0v without signal (that's the BLON line, which turns on the backlight).
Bad news : the screen I have is cracked. Sorry.

The connector is marked? I mean, has the GND, BL_ON, etc. signs or not? I can't remember if they are marked.

[EGuevarae]

Re: Samsung 910t

I just found this notes from a 173s, which uses almost the same (OK, it is the same ....) PSU/Inv as your unit.
The "gray" in the note should be the "red" in your PSU.


I don't know if your PSU would give 13v instead of 12 because of the 17->19" difference.
Pins 1 & 2 are dimming and BLON.

[Wizard]

Re: Samsung 910t

Still 13V, usually kind of high 12 voltage. I remember that for 17 & 19 because I repair these LCDs as authorized samsung shop.

Cheers, Wizard

[IRShifty]

Re: Samsung 910t

I'm getting 9v on all of them, don't know how, but i am.

[Wizard]

Re: Samsung 910t

Can we have detail again?

What capacitors are used to replace and did this PSU get complete do-over with electrolytic capacitors? Little ones too.

Cheers, Wizard