TM 1-1520-238-T-6
9–440
Change 3
9–189. CIRCUIT PROTECTION SYSTEM (AC ESSENTIAL BUS 2 – PILOT STATION) –
9–189
MAINTENANCE OPERATIONAL CHECK (cont)
1. Perform the maintenance operational check as follows:
Task
Result
a. On pilot aft circuit breaker panel (fig. 9–166),
open the following circuit breakers:
ECS ICE DET HTR (CB212),
ECS AFT FAN (CB75),
ECS FAB FANS (CB88),
POWER XFMR RECT 2 (CB4),
ECS CANOPY ANTI ICE (CB78),
POWER ENG 2 (CB44),
POWER BATT CHGR AC (CB86).
b. Detach P3 and P4.
c. Check for short between:
P3-D and ground,
P3-E, and ground,
P3-F and ground,
P4-A and ground,
P4-B and ground,
P4-C and ground.
If short exists, go to paragraph 9–191.
d. On pilot ELEC PWR panel (fig. 9–165), set
BATT/EXT PWR switch to EXT PWR.
M69-190
BATT / EXT PWR
SWITCH
Figure 9–165.
Pilot ELEC PWR Panel
e. Check for 115 VAC at (A402):
J3-D,
J3-E,
J3-F.
If 115 VAC is not present, go to paragraph 9–12 to
troubleshoot ac electrical power generation.
f. Check for 115 VAC at (A402):
J4-A,
J4-B,
J4-C.
If 115 VAC is not present, go to paragraph 9–12 to
troubleshoot ac electrical power generation.
