TM 1-1520-238-T-6
9–518
9–242. ASE DC CIRCUIT BREAKER (CB28) – DOES NOT STAY CLOSED
9–242
OR 28 VDC IS NOT PRESENT AT P1-34
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 1-1520-238-T-7
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 ASE DC circuit breaker (CB28) stay
closed.
YES
Go to step 4.
NO
Go to step 2.
2. Open CB28. Set BATT/EXT PWR switch to OFF.
Check for short between P1-34 and ground.
Does short exist?
YES
Go to step 3.
NO
Refer to TM 1-1520-238-T-7 to
troubleshoot DASE.
3. Detach wire at CB28-2. Check for short between
P1-34 and ground.
Does short exist?
YES
Repair shorted wire between
CB28-2 and P1-34.
Go to paragraph 9–233.
NO
Replace ASE DC circuit breaker
(CB28) (TM 1-1520-238-23).
4. Set BATT/EXT PWR switch to OFF. Check for
open between CB77-1 and P1-34.
Does open exist?
YES
Go to step 5.
NO
Replace ASE DC circuit breaker
(CB28) (TM 1-1520-238-23).
5. Check for open between CB28-2 and P1-34.
Does open exist?
YES
Repair open wire.
Go to paragraph 9–233.
NO
Replace bus bar between CB28
and CB77, and check for foreign
material (TM 1-1520-238-23).
END OF TASK
