dit vond ik op de elo site. http://media.elotouch.com/pdfs/manuals/intelli.pdf
IntelliTouch Serial Controllers The IntelliTouch serial controllers have one green diagnostic LED.
Following power on, the controller performs a short self-test, where the LED stays lit.
After the self-test, the LED flashes once per second, indicating normal operation.
The self-test results are displayed by most Elo driver software.
During normal operation, the LED also indicates controller/host communication is in progress.
When the touchscreen is touched, the LED should light continuously, then return to the normal flash rate.
If the host does not remove the packet from the controller, the LED will stay lit.
The LED will also stay lit without a touch if the touchscreen or cabling is disconnected or not functioning.
If the LED flashes about two times per second, a warning error condition is indicated, such as improper communication from the host. Suspect an invalid command sequence from the host.
Het lijkt er dus sterk op dat de pc de signalen niet ontvangt.