TM 55-1510-219-MTF
c.
Defective components.
F6.
One autofeather arm light illuminates when power
setting is less than 90 percent NI (AUTOFEATHER switch
in ARM position).
a.
Defective or out of adjustment power switch.
F7.
Neither autofeather arm light illuminates when power
levers are advanced (AUTOFEATHER switch 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 switch.
b.
Defective No. 1 (12 PSI) torque pressure switch.
F9.
Both arm lights remain illuminated when one power lever
is retarded (AUTOFEATHER switch in ARM position).
a.
Defective or out of adjustment power switch.
b.
Defective torque pressure switch.
F10.
Propeller does not start to feather after engine torque
falls below 9-14 percent (AUTOFEATHER switch in ARM
position).
a.
Defective No. 2 (6.5 PSI) torque pressure switch on
retarded engine.
b.
Defective autofeather dump valve.
F11.
One arm light does not illuminate when power levers are
advanced to 90 percent N1 (AUTOFEATHER ARM-TEST
switch in TEST position).
a.
Defective No. 1 (12 PSI) torque pressure switch.
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