TM 1-1520-238-T-6
9–547
9–263. CIRCUIT PROTECTION SYSTEM (DC EMERGENCY BUS – PILOT STATION) –
9–263
MAINTENANCE OPERATIONAL CHECK(CONT)
1. In aft avionics bay, check that CB148 is closed and battery is connected.
2. Perform the maintenance operational check as follows:
Task
Result
a. Detach P1, P5 and P463.
b. Check for short between :
P5-1 and ground,
P5-2 and ground,
P5-3 and ground.
If short exists, go to paragraph 9–265.
c. Check for continuity between (A76):
J1-h and J1-B.
If continuity does not exist, go to paragraph 9–266.
d. Check for continuity between (A76):
J1-h and J1-A.
If continuity does not exist, go to paragraph 9–267.
e. Check for continuity between:
P5-2 and P5-1,
P5-2 and P5-3.
If continuity does not exist, go to paragraph 9–268.
f. Check for continuity between
P5-2 and P5-4.
If continuity does not exist, go to paragraph 9–269.
g. On pilot ELEC PWR panel (fig. 9–190), set
BATT/EXT PWR switch in EXT PWR.
M69-250
BATT / EXT PWR
SWITCH
Figure 9–190.
Pilot ELEC PWR Panel
h. Check for 28 VDC at (A402):
J29-1,
J29-2,
J29-3.
If 28 VDC is not present, go to paragraph 9–23 to
troubleshoot dc electrical power generation.
i. Check for 28 VDC at (A76)J1-h.
If 28 VDC is not present, go to paragraph 9–266.
j. On pilot ELEC PWR panel, set BATT/EXT
PWR switch in OFF.
