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I am currently trying to repair a pen-tablet-monitor, which has what i call a 'blind/dead row'.
Meaning that i can draw everywhere, but there is this one row, where any input is either picked up by a row above, or below.

I visualize what a drawing would look like:
The red strokes symbolize the borders of the 'dead row'.

example of drawing with dead row

I stumbled upon this video fixing dead areas on graphics-tablet and tried cleaning any connections using isopropanol, but it didn't solve the issue.

But i took a closer look and found something, which seems strange to me. On the PCB that receives input from the sensor-board via a ribbon-cable(34P), there seems to be a solder-bridge between two of the pins. I tried my best taking a picture of it:

Solder-bridge

Now to my question (finally):

Might this not be something which is done by accident, but something that is actually fulfilling a purpose?
Are there cases, where something like this is used consciously (i.e. soldering together two pins directly after the interface)?

I really don't want to de-solder this connection until i can be reasonably sure, that it is the unwanted solder-bridge that i think it is.
Thank you!

edit: I was asked to provide further(better) images, and here they come: Also this time i took a closer look at the pcb, and well... these two pins don't even have two separate traces, but one connected.. at least this is what my nooby self is seeing.

close look look from further away

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Your photo is too fuzzy to tell if there is a trace connecting the two pins.

One thing is certain:

If your tablet/monitor ever worked correctly, then this bridge isn't the cause of your problem.

That bridge didn't spontaneously appear. It also didn't just suddenly start causing problems. That bridge looks to have been there since day one.

You need to look elsewhere for the cause of the problem.


Bridges like that form between pins that are close together. They most often form between pins that are connected together with a short trace.

The manufacturers usually have the processes well enough in hand that you would only get bridges on places where you want them.

Mistakes do happen, it would usually cause a larger problem than the subtle error you mention.

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  • \$\begingroup\$ The photo is shot via a camcorder, through a magnifying lens. It's the best i could achieve so far, but i might give it another try. I just bought the monitor via ebay, markes as 'overhauled'. When i noticed the problem, i could have returned it, but couldn't stop myself from disassembling it.. ;) So there is definetely the possibility of this problem being there since day one, existing without being noticed by anyone. But thanks for the cautious words.. It is thoughts like that which make me hesitate as well.. \$\endgroup\$ – LeonTheProfessional Apr 7 '19 at 14:49
  • \$\begingroup\$ There is no trace to the second pin, and the first pin is clearly connected to ground. It would be reasonable to have to ground pins next to each other (more current capability,) which is another reason to think the pins belong together. \$\endgroup\$ – JRE Apr 7 '19 at 15:00
  • \$\begingroup\$ If it were me, I'd clean it up and be done with it - but I can do that kind of thing in my sleep. And, I could probably tell by looking if both pins were supposed to be connected \$\endgroup\$ – JRE Apr 7 '19 at 15:02
  • \$\begingroup\$ By 'cleaning it up' you mean removing the soldering-iron in between? I will make a better shot, or short recording, but have to charge my aputure first.. will be posted in the course of the day. Thanks for your help so far! \$\endgroup\$ – LeonTheProfessional Apr 7 '19 at 15:14
  • \$\begingroup\$ Took a bit longer, but now i provided further images. I would be grateful, if you could shortly confirm or refute my interpretation, that there is only one trace going out from these two pins, and therefore this solder-bridge is very likely to be done on purpose. If anything else appears to you on these images, i would be happy to know as well. Thanks! \$\endgroup\$ – LeonTheProfessional Apr 8 '19 at 19:27
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I'm thinking that solder bridge is deliberate. There is not a trace leading away from the inner pad.

In addition, if the unit ever worked correctly in the past, that solder bridge could not be the cause of the problem.

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  • \$\begingroup\$ Thanks for your assessment. Note my comment under @JRE 's answer though, regarding the question of 'if the unit ever worked correctly in the past'. I can't tell, because i bought it from ebay. The fact that there is only one trace for those two pins also changed the way i interpret this bridge. Didn't look thoroughly enough when i first noticed the bridge. \$\endgroup\$ – LeonTheProfessional Apr 8 '19 at 21:20

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