Problem with touchscreen EPK-i

Have you checked the service or user manual?

Soma Technology or iMed Biomedical may be able to help you.

I would double check all connections on the cable and maybe reset the card. There maybe a loose connection somewhere. 

JPowell i've already checked more than ten times all connections, but i don't know how to reset the card, can you explain me please?

I believe they meant reseat. These things usually have some corrosion inside the unit. You can try reseating the card, or possibly cleaning the contacts.

If there is noticeable oxidation of board contacts, a regular pencil eraser will usually take care of it on the board contacts. Be sure to clean up the debris left by the eraser. A contact cleaner pen will clean both contacts at once

Did you try other scopes as well?