Does 912iS ECU use any data from static system?

AFAIK the motor ECU does not receive data from any aircraft system. The ECU measures air pressure at the air filter and in the manifold. Thats both sides of the throttle body if you like.

Thanks, Geoffrey! 

Rotax Wizard and Roger Lee, would you please be able to confirm this? 

The iS has no tie to the aircraft static ports.  They use only 2 MAP sensors in the airbox for pressure and one outside temp and pressure for a reference pressure.  These are all displayed in the ECU data stream.  

That said check the installation manual as the ambient pressure sensor of the ECU for the engine, its location, can affect if it works correctly.  ECO is not purely a reference to RPM or throttle position and is mapped within the program design.  The easiest reference for the pilot is to have your display show you the TPS position and normally it will go to ECO at about 96 or 97%.  This however can be affected by the load of the MAP to throttle also.  

Cheers

Thanks, Rotax Wizard! I've noticed that my 912iS always kicks into Eco Mode at 98% throttle. Is there anything wrong with that rather than at 96 or 97%? 

no problem really.  could just be the position you have your ambient temp and pressure sensor mounted at.  Most it will be about 97.  you may find this changes with density altitude.  

Cheers