TM 55-1510-221-MTF
a.
Battery switch left ON.
b.
Generator control unit set too low.
c.
Internal connection links loose.
d.
External connector burned or pitted.
e.
Defective or reversed cells.
f.
Cell case current leakage.
C12. External power fails to energize aircraft.
a.
Defective or incorrectly polarized external
power source.
b.
Defective external power receptacle
c.
Defective external power relay
d.
Loose or wrong connection In external pow-
er circuit.
e.
Defective external power overvoltage moni-
tor.
f.
APU voltage too high.
g.
Defective switch.
h.
Circuit breaker tripped.
C13. Landing gear will not retract or extend.
a.
Landing gear relay circuit breaker tripped.
b.
Landing gear power circuit breaker tripped.
c.
Landing gear power safety control circuit
breaker tripped.
d.
Landing gear power and sense circuit break-
er tripped.
e.
Landing gear safety power circuit breaker
tripped
f.
Faulty power pack motor.
g.
Faulty power relay.
h.
Faulty remote-controlled circuit breaker
(RCCB).
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