WACOM Cintiq 21UX - LCD issue

[DRen]

Hello!
I'm hoping to find some insight for solving an issue with my old, old, old WACOM Cintiq 21UX.
Yesterday, my heart sank as this trusty piece of hardware, after more than 10 years of excessive, daily use (Impressive to be honest) could provide me with no more than a black screen. The morning, it worked BUT, I did take notice in how it started out quite dark, as if it had been in sleep mode and needed a moment (this has happened before, if the UI was slow to boot, following an update or so), thus I didn't think too much of it.
This forum is no the stranger to this "beast", which is how I found this place, from earlier posts dating back to 2010 asking for repair advice.

I can afford a brand new... but only just barely, like, I'll be dining on wooden shavings from old furnitures for a while, if I replace.

INFO:

• The device Powers On. (Automatically switches on from standby when the Computer attached, is on).
• Assuming the pen functions and buttons are working as well.
• The Backlighting functions and triggers as it has always done (going on/off accordingly to the state of the device)
• Nothing smells or looks burnt (just... 10 year old well-used circuit boards receiving a daily dose of electric warmth)

However, the issue is that the LCD screen remains black. I'm sure I can confirm it's the screen, as it would normally function even without a computer attached, but give a little message in a box that it was receiving no signal and would enter Sleep Mode. Even this box no longer appears, which I'm guessing would indicate that the LCD screen is no longer receiving a signal.

I'm providing some pictures, but I really must apologize for the quality, as the loss of this hardware has nearly set me back to the Stone Age.
For better and clearer ones (with component info added), I can direct your attention to the 7 and 5 year old posts:

• Need help with a Wacom Cintiq 21UX monitor (Reverse polarity applied) - SOLVED
• Schematic Wacom Cintiq 21ux

I can solder, but don't have much experience when looking for faults on something like this, so I would like to know and get an idea of where to start. Ideally, it's just a small transistor that has seen the end of its lifetime, which just needs to be replaced.
(here's to hoping)
Thank you for your time!

First image is the layout with the two suspects marked.
Second image is the primary board in the center where everything comes together.
Third image is the LCD circuit. This would get cozily warm! (but never burning)

 

[shrtrnd]

Hopefully you'll receive some advice from somebody familiar with your model. My opinion is that your LCD has reached the end of it's life-span. I'd be looking into the possibility of a replacement.

 

[kellys_eye]

Backlight failure is the usual suspect. If you hold a torch to the screen you may be able to see the image.....

It could be thebacklight driver board or the backlights themselves - the former being repairable, the latter 'is' repairable but often sourcing the CFL's is difficult although there are many CFL-to-LCD conversions available these days too.

The CFL driver is under the screening can on the right of your images. Pop the lid off and show us a close-up, in-focus image of the board.

 

[DRen]

The CFL driver is under the screening can on the right of your images. Pop the lid off and show us a close-up, in-focus image of the board.

This one, correct? If you need one with better focus, I can have a look around as see what I can do.

 

[DRen]

Hopefully you'll receive some advice from somebody familiar with your model. My opinion is that your LCD has reached the end of it's life-span. I'd be looking into the possibility of a replacement.

Trying the best I can to avoid a full replacement. Although it would be nice; this screen... after 10 years of usage, imagine the amount of scratches on the display! I can't take a photo of that at the moment, due to its current position.
Also, the tablet came with a bundle of replacable pen tips. They are all worn down, pretty much. Usable, but not in a prime condition.
Overall, it would be due for a replacement, but I current have around $1500 to make the most out of. The currently cheapest one I could find would total up for $1153 (from $800, pre-shipping/import fees).

 

[kellys_eye]

My bad... that looks like the screen digitizer board. Need a better (in focus) image of the whole setup to determine which is which.

 

[DRen]

My bad... that looks like the screen digitizer board. Need a better (in focus) image of the whole setup to determine which is which.

Indeed it is. But I figured you may have still wanted a look-see.

Again, I apologize for the qualities. I really don't think I'll be able to take any better ones for today.
I've compiled together (in MS Paint, wow. Since my graphics machine is obviously out)
It can be a bit difficult, since everything is so neatly packaged up inside the screen.

 

[kellys_eye]

I can see a connector that shows 'backlight circuit' going off to ???? the board I need to see!

 

[DRen]

I can see a connector that shows 'backlight circuit' going off to ???? the board I need to see!

The lighting is getting remarkably bad here now. But yep, this should be for the backlighting, which I do not suspect any problems with, as I described, it turns on/off. (screen goes from black, to "less black" and the outer rim of the screen gets lightly illuminated.

 

[HellasTechn]

It could be thebacklight driver board or the backlights themselves - the former being repairable, the latter 'is' repairable but often sourcing the CFL's is difficult although there are many CFL-to-LCD conversions available these days too.

If the problem is one of the CCFL lamps snand you can not find a replacement then you could convert it to LED backlight.

Usually when CCFL fail the symptom is that the backlight comes on and goes off one second later.

 

[kellys_eye]

Tried a replacement video lead yet?

<edit> Hellas makes a good point re the backlight coming on, but briefly.....

 

[DRen]

If the problem is one of the CCFL lamps snand you can not find a replacement then you could convert it to LED backlight.

Usually when CCFL fail the symptom is that the backlight comes on and goes off one second later.

Hmm, I'm honestly not sure what you mean, but I may have described it poorly in my previous reply.
I do not experience any issue with the backlights what so ever.
What I mean with that they turn on/off, is that they function as intended: When the PC is connected to the screen and is switched on, the Cintiq 21UX wakes up from standby AND the backlights comes on as well. The screen is still "black", but the entire thing has a slight glow to it. Like, you are fully able to see the screen in the dark.
The backlights respond as they always have. They power on when the PC comes on. They power off briefly, with the PC is done with its little boot-up, whereafter they come back on, as soon as Windows pops on screen.

I can and have found a potential replacement, but as mentioned, my funds are limited (I can afford it, but it will be cutting it close), furthermore, it would take nearly a month for it to arrive here, which is not desired. (got work to finish! )
I also found a dirt-cheap Cintiq 21UX that is broken and suggested "sold as/for parts". I would love to buy that and replace the suspected faulty circuit boards, but that would be gambling... I don't know HOW it's broken and could potentially suffer the same as mine currently is.

 

[kellys_eye]

So the screen backlight works but there is zero data displayed? No data displayed when the on-screen menu buttons are pressed?
Are there alternative input ports on the device to try?

When faults like this occur in TV's it is usually the TCON board at fault. Sourcing a replacement for that particular model MAY be possible but is unlikely. Sadly.

So, faced with the symptoms you describe I'd check that all the relevant DC supplies were present thereafter be looking at the changing the TCON board before anything else.

 

[DRen]

So the screen backlight works but there is zero data displayed? No data displayed when the on-screen menu buttons are pressed?
Are there alternative input ports on the device to try?

When faults like this occur in TV's it is usually the TCON board at fault. Sourcing a replacement for that particular model MAY be possible but is unlikely. Sadly.

So, faced with the symptoms you describe I'd check that all the relevant DC supplies were present thereafter be looking at the changing the TCON board before anything else.

As described, not even the native on-screen menu and/or info boxes will appear, like the one appearing when the computer is off or none are attached at all, the classic "no signal going to sleep".

I have attempted to look for a cheap replacement TCON board but haven't really had any luck. Obviously, as it's a pretty specific board. (3rd image in my original post).