TM 55-1510-215-MTF
F5.
Annunciator panel secondary stop lights illuminate
during normal propeller reversing.
a.
Defective secondary low pitch power lever switch.
F6.
One propeller does not govern at specified RPM
during propeller governor tests.
a. Defective propeller governor secondary low pitch
stop test switch.
F7.
Propeller
autofeather
system
completely
inoperative
(propeller autofeather switch in ARM or TEST position).
a.
Tripped circuit breaker.
b.
Defective arming light out relay or feathering relay.
c. Defective arc suppression diode on relays or feather
dump valve.
d.
Defective ground blocking diode.
F8.
Autofeather circuit breaker trips (auto-feather switch in
ARM or TEST position).
a.
Defective ARM-TEST switch.
b.
Defective wiring.
F9.
One autofeather arm light illuminates when power setting
is less than 90 percent N1 (AUTOFEATHER switch in ARM
position).
a.
Defective or out of adjustment power switch.
3-30
