Hi, I got the same problem as most of you, touch screen died suddenly (RU 950). As Pronto is crucial in my HT I even bought a new one (RU950). After that I could start to analyse the problem in the old one with a good concience! And alas, I found the fix, which will cure both dead screen but also the failing calibration (actually the same basic cause). BTW If the Pronto Team doesnt really know the problem - I am disappointed. The nice thing about the fix is that it does not cost anything, but you have to be able to open the whole plastic cover system properly.
Disclaimer: I do not take any responsibility of this fix - you try it at your own risk!
First you have to open the plastic cover system (there are 5 torx screws holding the upper part, 4 visible and one inside). After that you may be able to take off the green rim round the touch screen. When that is done, you will see a flexible connector (carbon to copper) at the upper right corner of the touch screen. And that is the cause of the problem! There are four connection points (o o o o) which should make contact with the flexible copper strips beneath them - but for some reason they lose their connectivity after some time (oxidation?). So the simple fix is to rub the connection points with a sharp object (model knife, opposite end of a needle). Be careful not to puncture the plastic (or break the glass!) but still use enough power to ensure a good contact... If only one connection point is faulty you will get calibration error, if more, the touch screen does not work at all. If Daniel allows, I could send some pictures to make it more clear to u all.
