Toptobottom, just a quick explanation that might shed some light. Screen 1 is the visual display of processor 1 and screen 2 the visual display of processor 2- 2 seperate computers. They each receive the primary info incase of a failure so you retain the primary info from the other processor. Each processor then have additional tasks ie 1 calculates the FLI and 2 The power check. So by excluding screen 2 you are excluding processor 2 which probably means processor 2 is gone. Unfortunately the processors can only be replaced by Thales thus the service exchange.