Bongofish

Screen Tablet malarky => Heyaaaalpppp => Topic started by: jedikalimero on August 04, 2017, 07:55:07 PM



Title: dropped 21UX 2nd gen not responding to stylus.
Post by: jedikalimero on August 04, 2017, 07:55:07 PM
I have a second generation Cintiq 21UX DTK-2100 and recently in a very unfortunate accident it fell to the floor being hit in the lower left corner. Yhe plastic case in that corner broke in pieces but the LCD is still intact and working correctly. The Wacom driver still detects the Cintiq and all the ExpressKeys and ExpressSliders work but it doesn't react at all when I touch the screen with the stylus. (I have tried with several styluses, Grip Pen, Airbrush, Art Pen, Grip Pen Pro, Classic Pen but no way. All of them working in Intuos Pro, 5 and 4, of course).

So I think the problem is located at the tablet driver board (identified as PWB-B034D) that is still partially working since the device itself is detected and all the keys and sliders work. Or either in the sheet under the LCD that makes the EM matrix, but this is less likely since it is just a sheet of printed circuit matrix without any components on it.

I guess Wacom would charge me more than the cost of a fully working second hand 21UX for the motherboard so any suggestions?
The Motherboard has LOTS of test points but I don't know how to test it since I haven't found any information about it.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: XDjackieXD on August 05, 2017, 08:36:50 PM
could you take some high-res photos of the insides? that would make debugging a bit easier.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: Ertew on August 05, 2017, 11:37:20 PM
I have two Tablet-PC screens.
T5010 have typical construction: single PCB for Wacom chips and flat-flex circuit for antennas.
ST5111 have two solid boards, one with chips, second with antennas. Both boards are connected via board to board connector.
If You have second option, then connector may just need to reconnect and that's all. If connector wasn't the problem I guess broken quartz oscillator (hard to replace in home, easy for electronic service). If still nothing then repair of broken digitizer may be impossible or even more expensive than new digitizer.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: XDjackieXD on August 06, 2017, 12:09:47 PM
well replacing an oscillator isn't hard but remotely diagnosing a defective oscillator is...


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: Ertew on August 06, 2017, 02:30:30 PM
Quartz oscillator is the most fragile component of most electronic boards (except displays and connectors).
Broken solder joints or traces on PCB may be unrepairable. Especially when board is attached to heat sensitive flex circuit (antennas).


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: XDjackieXD on August 07, 2017, 06:49:28 PM
Oh oscillators are not *that* fragile. I abused some of them quite a bit but they are fragile compared to most other components on a board ^^


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: Pesho on August 08, 2017, 04:02:05 PM
Those things are solid-state components, i doubt it's that. AFAIK the buttons and sliders are separate boards that connect to a board that's located on the left side. Better check it for loose connections and broken off SMD components. My bet is that there's no connection between that board and the actual digitizer grid that's located behind the screen.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: Ertew on August 08, 2017, 04:41:06 PM
Yeah. All we can do at this moment is wait for more info or photos and keep guessing :)

XDjackieXD: You have different experience than me. Can You wrote Your guesses what may be wrong?


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: XDjackieXD on August 09, 2017, 03:00:39 PM
XDjackieXD: You have different experience than me. Can You wrote Your guesses what may be wrong?
Well I don't know the wacom boards but usually board to board connectors and cold solder joints are what fail after a drop (at least that's my experience with stuff like audio mixers, laptops and many other things I repaired so far)


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: jedikalimero on August 16, 2017, 07:03:19 PM
Hello again.
Here are the pictures. I took several more pictures than needed just in case they help to somebody else needing to disassemble a DTK-2100.

[attachment=1]

[attachment=2]

[attachment=3]

[attachment=4]

[attachment=5]

[attachment=6]

[attachment=7]

[attachment=8]

I have checked the connection between the Cintiq motherboard and the Display controller, not only pint to pin but following the tracks to the first component connected to each pin and it is OK, so the problem MUST be located in the Cintiq motherboard or the sensor matrix.

But in case the problem was in the sensor matrix, I guess I would get vertical or horizontal areas in the screen where the pen is not detected but not a complete lack of response everywhere.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: jedikalimero on August 16, 2017, 08:48:48 PM
Here are a couple of HI RES pictures I took of the motherboard using a scanner:


(http://i.imgur.com/2Xd3krjm.jpg) (http://imgur.com/2Xd3krj)

(http://i.imgur.com/xTLuVbDm.jpg) (http://imgur.com/xTLuVbD)



Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: Ertew on August 16, 2017, 10:39:51 PM
As I see, digitizer board have two main chips and strange connector to LCD board.
First chip, lets say USB chip, working fully or partially. USB and buttons working. Communication with second chip may be broken.
Second chip, let say Digitizer chip, may be broken or waiting for signal from display controller.

IMHO both boards may need repair.


Title: Re: dropped 21UX 2nd gen not responding to stylus.
Post by: jedikalimero on August 17, 2017, 02:50:50 AM
As I see, digitizer board have two main chips and strange connector to LCD board.
First chip, lets say USB chip, working fully or partially. USB and buttons working. Communication with second chip may be broken.
Second chip, let say Digitizer chip, may be broken or waiting for signal from display controller.

IMHO both boards may need repair.

U5 is M16C R5F36CAMNFB and is the chip connected directly to the USB D- and D+ signals (through resistors). It is a microcomputer with its own memory, DMA, etc commonly used in USB devices.
U6 is the Wacom chip W4027F. This is the chip that locates the stylus and processes the signals from it. It is also present in the Intuos tablets.