System Maintenance Manual

Page 2-4 G1000/GFC700 System Maintenance Manual – C90A/C90GT/C90GTi King Air
Revision F 190-00682-01
2.1.6 GEA 71 Engine/Airframe Unit (2)
The Garmin GEA 71 Engine/Airframe Units provide engine/airframe data to the G1000 system. Data
received from transducers/sensors is processed and sent to GIA 63Ws (via RS-485 digital interface), and
subsequently to the GDU 1500 MFD. Engine parameters are normally displayed on the MFD. In the event
of MFD failure, the engine parameters can be displayed on PFD 1 and/or PFD 2 using display reversion.
The GEAs are located behind the instrument panel and are mounted in a vertical orientation. Power is
received from the triple-fed bus. Both GEA units will power-up immediately with external or aircraft power
or battery operation.
Each GEA interfaces to the following sensors for its onside engine:
• Oil Pressure Sensor
• Oil Temperature Sensor
• Fuel Flow Sensor (via onside Signal Conditioner)
• Turbine Speed Sensor (via onside Signal Conditioner)
• Propeller Speed Sensor(via onside Signal Conditioner)
• Torque Sensor
• Interstage Turbine Temperature (ITT) Sensor
2.1.7 GTX 33 Mode S Transponder (2)
The GTX 33 Non-Extended Squitter or GTX 33 Extended Squitter (ES) (Optional) transponders
communicate with the on-side GIA 63W through RS-232 digital interface. The units are mounted in the
nose equipment bay. Power is provided by the No. 1 and No. 2 avionics bus for GTX 33 No. 1 and No. 2
respectively. The GTX 33 units interface with the existing transponder antennas.
NOTE
A model designation of GTX 33 in this manual will imply either the GTX 33 Non-Extend Squitter or GTX
33 Extended Squitter (ES) transponder.