PRESSURIZED AIR SYSTEM MAINTENANCE OPERATIONAL CHECK (cont)
PAS components get hot during operation. To prevent possible burns,
avoid touching hot surfaces. If injury occurs seek medical aid immediately.
6. Complete the maintenance operational check as follows:
a. With ENCU switch on pilot ECS panel (fig.
752) set to ON, start/operate APU
(TM 1-1520-238-CL). On pilot center circuit
breaker panel (fig.753), check FUEL BST
circuit breaker stays closed. On pilot
caution/warning panel (fig.754), check that
SHAFT DRIVEN COMP indicator remains
lighted approximately 60 seconds after APU
If FUEL BST circuit breaker does not stay closed, go
to paragraph 747.
If SHAFT DRIVEN COMP indicator is not lighted for
approximately 60 seconds after APU start, go to
If SHAFT DRIVEN COMP indicator remains lighted
longer than approximately 60 seconds after APU
start, go to paragraph 749.
If APU fails to start, refer to TM 1-1520-238-T-8 to
Pilot ECS Panel