Supplement Airplane Maintenance Manual
Cessna 172 with TAE 125-02-99 / -114
AMM-20-02
Chapter:
Issue:
Issue Date:
Page:
Content:
20-AMM-71-02
3
06.11.2013
6
46
Rev. No:
Rev. Date:
1
25.08.2014
Electronic and Electronical System
The engine is controlled via a 32-bit Microprocessor Engine
Management system (FADEC) incorporating redundancy. The
FADEC consists of two complete and identical redundant halves
and the most important sensors (Cam and Crank signals) are
redundant as well. An intelligent control strategy manages
switching between the two redundant FADEC channels in case
of a failure. All sensor signals are continuously monitored, sensor
failures are detected automatically and the control strategies
account for sensor failures. The FADEC is equipped with two
warning lights (one for each redundant half) that constitute the
means to alert the crew of failures and when crew action is
needed.
An event log store logging all failures and extreme sensor input
values as well as an integral hours run meter ensure maximum
safety against potentially damaging events. An independent
safety system monitors the stored events before every take off
and independently makes a check of all functions including a
switch to the other redundant half to make sure both FADEC
channel are in working order. The control system includes a data
stream interface implemented as a CAN line that carries several
sensor and FADEC internal values and can be used to drive an
engine instrument like the CED-125.
Figure 71.1 FADEC overview
CAN BUS
Crank Sensor
CAM Sensor
Injector 1
Injector 2
Injector 3
Injector 4
Railvalve
Boostvalve
Glow Control
2 x Check Engine Lamp
CAN BUS
Load-Poti
Airtemperature Sensor
Railpressure Sensor
Oil pressure
BARO-Sensor
MAP-Sensor
ECU Test Switch
ECU A/B Switch
Gear Temperature
(Prop Pressure)
Watertemperature Sensor
Oil Temperature
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Integrated Sensors (redundant)
CED
Laptop with
CAN Interface
TAE 125 FADEC
Overview
Issue 11/02
(Fuel Temperature)
Propvalve
Содержание Cessna 172
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