Hi Clare,
When working at Hope Hosp. we had over 8 failures of the GUI bd.
The faults ranged from complete failure to that which you described.
After much debate with Coviden, and a good chunk of money, we decided to carry out our own investigation.
It turned out that the power supply to ICU was a bit spikey and as all cableing came through the pendant this was being inductively coupled to the data lines causing the varied failures to the GUI.
We fitted RS 232 opto isolators to the data line and left them permanantly connected, cost around £8.00 ea, think we got them from CPC.
From then on we had no further failures.
Hope this helps.
