EFI warning and red light
Aprilia Caponord 1200, Travel Pack, 2014 model. Have read this thread with interest and have the same issue. With standard exhaust, red light and EFI warning light came on, while riding back to UK in Switzerland. Bike performed normally. On return, dealer diagnosed sticking exhaust valve. Job done. Have since had a GPR silencer fitted; dealer fitted and upgraded to latest software map, then verified with the new silencer. With this unit, the exhaust valve cables are removed. Bike tested out OK by dealer.
Have just returned from a trip to Switzerland. EFI warning and red light on for most of the trip. Bike performed admirably, without any performance degradation. I have not used the E10 fuel, preferring to stay with standard RON95 unleaded. With a cool engine, the warnings go out, after reaching operating temperature (typically 10-30 minutes) EFI and red light come on.
Given no exhaust cables or exhaust valve is currently in place now, it will be interesting to hear of the diagnosis, presumably: either the servo unit is faulty or the ECU is still in need of further updates. GPR UK distributor, GPR Italy and the Aprilia dealership have been very supportive throughout.