TM 1-1520-238-T-6
9–399
9–158. MISSION PC AC CIRCUIT BREAKER (CB51) – DOES NOT STAY CLOSED OR 115 VAC
9–158
IS NOT PRESENT AT P1-28
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68X
Armament/Electrical Systems Repairer
One person to assist
References:
TM 1-1520-238-23
TM 9-1230-476-20-2
WARNING
Turn off power before detaching or
attaching wires and connectors. High
current 28 VDC or 115 VAC is present.
Failure to do so could result in death or
serious injury.
1. On pilot ELEC PWR panel, set BATT/EXT PWR
switch to EXT PWR.
Does MISSION FC AC circuit breaker (CB51)
stay closed?
YES
Go to step 4.
NO
Go to step 2.
2. Open CB51. Set BATT/EXT PWR switch to OFF.
Check for short between P1-28 and ground
Does short exist?
YES
Go to step 3.
NO
Refer to TM 9-1230-476-20-2 to
troubleshoot MRTU.
3. Detach wire at CB51-2. Check for short between
P1-28 and ground.
Does short exist?
YES
Repair shorted wire between
CB51-2 and P1-28.
Go to paragraph 9–150.
NO
Replace MISSION FC AC circuit
breaker (CB51)
(TM 1-1520-238-23).
4. Set BATT/EXT PWR switch to OFF. Check for
open between:
CB51-1 and CB92-1,
CB51-2 and P1-28.
Does open exist?
YES
Repair open wire.
Go to paragraph 9–150.
NO
Replace MISSION FC AC circuit
breaker (CB51)
(TM 1-1520-238-23).
END OF TASK
