TM 1-1510-225-MTF
c. Defective switch.
F3.
d. Defective propeller governor reset solenoid.
Propeller governor test system inoperative on one
engine.
a. Defective PROP GOV test switch.
F4.
b. Defective propeller governor reset solenoid.
Propeller autofeather system inoperative (propel-
ler 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.
F5.
d. Defective ground blocking diode.
A U T O F E A T H E R c i r c u i t b r e a k e r t r i p s
(AUTOFEATHER switch in ARM or TEST posi-
tion).
a. Defective ARM-TEST switch.
F6.
b. Defective wiring.
One AUTOFEATHER arm light illuminates when
power setting is less than 90 percent N,
(AUTOFEATHER switch in ARM position).
a. Defective or out of adjustment power lever
switch.
F7.
Neither AUTOFEATHER arm light illuminates
w h e n P O W E R l e v e r s a r e a d v a n c e d
(AUTOFEATHER stitch in ARM position).
a. Defective AUTOFEATHER switch.
F8.
One arm light does not illuminate when POWER
levers are advanced (AUTOFEATHER switch in
ARM position).
a. Defective or out of adjustment power lever
switch.
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