Can't tell if is the old version, anyway is manufactured in 2013
Actually I have some additional info, don't know if could help to troubleshoot this before opening the 3ds (which I would like to leave as last resort)
You know those "games" where you have to write japanese kanjis? (kanji training games, like
kanken training 2)
If the power cable is attached to the 3ds, the writing is not smooth, like if somethimes the touchscreen "skip" reading the input and so if you try to do a line, you get a dashed line.
But when the power cable is disconnected, then the writing becomes smooth.
Also, once I tried to turn on the 3ds while the power cable was attached, the blue led flashed for an instant and nothing happened, and 3 subsequent attempt to turn on the 3ds failed, even after unplugging the cable, it didn't turned on. So I kind of waited, then I tried to hold the power button, the led fleshed blue and then red, and then on the next attemp of turning it on, it worked.
So...Any guess about what's going on? :S